So...
1 fish @ 500g per 20L of filtration, or 2.5% of the media in fishmeat by volume (fish being neutrally buoyant equal water weight by volume (1 ml of water = 1g) seems like a reasonably common stocking level.
...
So for every 20 L of growbed media (gravel, clay balls etc) you can stock 1 fish that you intend to grow out to plate size.
Plate size is considered to be 500g, and reflects what a restaurant might like to serve a customer on a plate rather than the actual size of your plate.
I dont know what size your plate is.
Although it's probably, by coincidence, roughly the same length as a "plate sized fish" wide.
Or high.
Anyway...
So a fish, that looks nice on a dinner plate, is around 30cm long, weighs around 500g, or a little over a pound, and requires around 20L or 5 ¼ gallons of filtration or grow media to support it throughout it's life of pumping fish crud into the water.
“Stop eating so much. You don't need that much protein in one meal.” I sometimes tell myself. But I'm wrong. Fish is delicious, so I'm probably going to keep eating that much.
So you put a stack of fish into your system, and you end up waiting quite a while, then you pull them all out, and put them in the freezer.
But fresh is best.
Why don't we eat smaller fish? Fish are crazy brave when they are young, and feed like mad taking all kinds of risks to get to the food before their fellow fishies. This means they grow quite quickly when they are young.
Trout and barramundi seem to grow to plate size in 8 months. But that might be because they are already quite grown up when you get them. Silver perch take around two years. Or actually two summers, as they dont feed a lot during winter. Most fish varieties grow quite fast at their preferred temperature.
So if our systems need the number of fish they can support to give the vegies their best conditions to impress, why do we have so few fish for so long.
Most people stock a number of fish that their system can cope with once they have grown to plate size. But that means the system is low on nutrients for the greater part of a year, and then perhaps overloaded for a bit, then suddenly, has no nutrients for the plants at all when the fish are all harvested.
The system's resident veggies must hate it.
But what this means is that you either have to supplement your ammonia, or nitrate inputs into the system with Charlie Carp (fishy goo) or something to keep the plants happy.
So, all that stuff is true.
But its also true that we eat fish that are smaller then a plate sized trout. Sometimes a lot smaller.
In South Australia, where I happen to be, we eat Australian Herring, Gar Fish, Leather Jacket, Yellow Fin Whiting, and almost every other fish we eat can be bought or legally caught at smaller than plate size. I think even our King Gorge Whiting, considered by many as one of the greats, are legally caught at less that “plate size”.
So what's so good about plate size?
Don't answer that, it's a rhetorical question. Unless there is actually an answer...
then …
go for it.
But...
Ideally we should stock our systems with 100% of their fish meat holding capacity, and start eating the biggest of the small fish the following week.
That could get a little finicky when trying to fillet a 4cm fingerling, but perhaps there is some kind of compromise.
Silver perch take two summers to reach plate size.
Perhaps we should stock an amount of silver perch, such that after one summer, there is enough fish by weight, that we are not over stocked, but that we can start eating. They grow slowly in the colder time, but that might mean we can slowly eat some in an attempt to keep the stocking level at close to optimum, and when the next summer comes, we still have the right amount of fish, but we can start eating more, more often, until we find ourselves with one last megafish, still capable of running the system.
Obviously rather than one mega fish, it would be better to buy more fry at a time when the system could afford ...say... 50 new fish, if there was one less big one in the system.
That should be the trigger for buying new fish.
After working out how many fish such a program would require to restock, approximate the big fish equivalent to the number of new fry, and restock when eating the big fish would allow enough filtration media, to buy a new batch of small fish.
This might seem obvious to some, but it doesn't seem to be normal practice.
Given the price of decent quality, ethically raised, organic, un-polluted, un-heavy metalled, fish, and the feed conversion rate of around 1:1.2 (ie 1.2 kg of feed makes around 1kg of fish (insects, algae etc make up some feed, and fish do a whole lot of floating perfectly still waiting for food to wander past them, so they are fantastically efficient(some trials have shown better than a 1:1 ratio))) …
where was I...
Given all that, and the fact that you pay a bit for your new little fish (around $1.80 for me) it still works out to be an exxcellent deal to eat the fish way before they are plate sized.
So...
I think I should try to work out how many fish I should buy to make this form of stocking a reality.
120 Things in 20 years needs to make a spreadsheet to work out a better aquaponics fish stocking density plan. Or just take a bit of an educated guess.
It's my intention to gain a new ability every 2 months for the next 20 years. I'd enjoy some company, some help, and some constructive criticism.
Things so far...
Animation
(5)
Aquaponics
(340)
Bread
(15)
Cheese
(16)
cooking
(49)
electronics
(57)
Epic adventurer
(20)
Escargot
(2)
Fire
(6)
Fraudster
(1)
Handmade fishing lures
(31)
Home made preserves
(11)
Making smoked foods
(11)
Mold making
(7)
Movie watcher and critic
(2)
Photography
(17)
PVC
(36)
Snail farming
(6)
Solar hot water
(26)
Solar photovoltaic panels
(7)
Stirling Engines
(11)
Thinking
(52)
Vermiculture
(1)
Wind energy
(26)
Aquaponics - Training tomato plants
I'm trying to teach my tomato a lesson.
I'm tring to teach it to play outside.
It's way too crowded inside my growhouse for a tomato plant, so I've decided it has to go outside.
There's a small triangle space that's near the top of the fishtank, which should alow for enough space.
To force it to grow that way, I thought I might try just leaning it over, and covering it.
The roots have come a little way out of the fish tank as a result of leaning it over, but there are still a lot that make it into the water.
It's been like this a few days now, and I think it's working.
Maybe.
The tomatoes do seem to be ignoring my wishes and growing up, but that might just be from habit.
It's hoped that they will find their way out of the corner and then down the side of the growhouse, but it might take a while.
120 Things in 20 years thinks the secret to training tomatoes is a firm but calm voice, and patience ... and an aquaponics system... and a blue tarp.
I'm tring to teach it to play outside.
It's way too crowded inside my growhouse for a tomato plant, so I've decided it has to go outside.
There's a small triangle space that's near the top of the fishtank, which should alow for enough space.
The roots have come a little way out of the fish tank as a result of leaning it over, but there are still a lot that make it into the water.
It's been like this a few days now, and I think it's working.
Maybe.
The tomatoes do seem to be ignoring my wishes and growing up, but that might just be from habit.
It's hoped that they will find their way out of the corner and then down the side of the growhouse, but it might take a while.
120 Things in 20 years thinks the secret to training tomatoes is a firm but calm voice, and patience ... and an aquaponics system... and a blue tarp.
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Aquaponics - Alf alfa sprout transplant test
I thought I'd test an alf alfa sprout transplant to see if there were going to be any issues.
The result was both a success and a fail.
I started with some normal alf alfa sprouts pulled from my sprouter device.
I figured half a dozen would be a good number to test.
I thought perhaps the shock of going from my perfect humidity, no wind, no real temperature swings, sprouting device might make them all kick the bucket when dropped suddenly into my aquaponics system.
The first one I planted was rested into a shallow hole made in the scoria. I figured I'd have to be pretty gentle with them because the scoria is a little rough.
I ate the rest, so I'm not sure this really qualifies as good science.
But after covering it up it looked like this.
I'm not sure if this pic is right after he transplant or the next day, but either way it looked like this the next day.
It was planted in the hottest part of a reasonably hot day, so I think it can be claimed as successful.
But the day after, it looked like this.
I had to dig around a bit to find it because whatever had eaten it, had eaten it down to beneath ground level.
I hate slugs.
120 Things in 20 years - And that folks, is why we should not eat the science, when testing sprout transplants in aquaponics.
The result was both a success and a fail.
I started with some normal alf alfa sprouts pulled from my sprouter device.
I figured half a dozen would be a good number to test.
I thought perhaps the shock of going from my perfect humidity, no wind, no real temperature swings, sprouting device might make them all kick the bucket when dropped suddenly into my aquaponics system.
The first one I planted was rested into a shallow hole made in the scoria. I figured I'd have to be pretty gentle with them because the scoria is a little rough.
I ate the rest, so I'm not sure this really qualifies as good science.
But after covering it up it looked like this.
I'm not sure if this pic is right after he transplant or the next day, but either way it looked like this the next day.
It was planted in the hottest part of a reasonably hot day, so I think it can be claimed as successful.
But the day after, it looked like this.
I had to dig around a bit to find it because whatever had eaten it, had eaten it down to beneath ground level.
I hate slugs.
120 Things in 20 years - And that folks, is why we should not eat the science, when testing sprout transplants in aquaponics.
Aquaponics - Capsicum sprout success (I think)
I'm still a little hesetant to sugest the capsicum sprouter tests have been a success becuase one of them is turning a little brown on the root tip.
But that might just be because I'm a little rough sometimes and put my camera on them when trying to take side on, macro shots, in a dish.
It might also that be it simply doesnt work.
But I think what I see here is a shoot that might just be long enough to plant in my system.
I'd guess it's around 40mm long, and I think I'd prefer to transplant it at more like twice that, but I also think I could get away with it now.
In fact I might even just be able to transplant them as soon as the seed is proven viable. ie when they are at the stage of the first sign of sprouting. I'd need to be gentle, but it might be doable. Especially in the clay ball media rather than the rougher scoria.
Either way, it looks like tis turning into a useful method of propergating seed for aquaponics, allowing for additional control over where plants grow and when, without having to add dirt to a system, or buy seedlings.
Just as an aside, when you transplant seedlings bought from a store, wash them realy well, because there's a fair chance they have been sprayed with...
well...
everything.
120 Things in 20 years - Moving gradually closer to some kind of success with some stuff to do with raising capsicum seeds in a bean sprout sprouter.
But that might just be because I'm a little rough sometimes and put my camera on them when trying to take side on, macro shots, in a dish.
It might also that be it simply doesnt work.
But I think what I see here is a shoot that might just be long enough to plant in my system.
I'd guess it's around 40mm long, and I think I'd prefer to transplant it at more like twice that, but I also think I could get away with it now.
In fact I might even just be able to transplant them as soon as the seed is proven viable. ie when they are at the stage of the first sign of sprouting. I'd need to be gentle, but it might be doable. Especially in the clay ball media rather than the rougher scoria.
Either way, it looks like tis turning into a useful method of propergating seed for aquaponics, allowing for additional control over where plants grow and when, without having to add dirt to a system, or buy seedlings.
Just as an aside, when you transplant seedlings bought from a store, wash them realy well, because there's a fair chance they have been sprayed with...
well...
everything.
120 Things in 20 years - Moving gradually closer to some kind of success with some stuff to do with raising capsicum seeds in a bean sprout sprouter.
Aquaponics - Sprouter capsicum falling over
The now 6 days old (from the time of first sprouting) capsicum sprouts in the sprouter are trying to reach up and put out some leaves, but they keep falling over.
This might not be a big deal, as it might just coil around a bit until it creates a stand for itself, and then goes about it's growy business.
The danger will be that by the time it creates a stand for itself, it will be out of energy.
As I understand it, the sprout grows only from the energy stored in the seed, and water from the environment. Some seeds need to get through quite a bit of dirt, so I'm hoping nature has left a little in reserve.
I guess they will still grow even if I transplant them as a coil, but I was hoping for a nice straight tap root to make sure it reaches the water in the aquaponics system.
It's normal in an aquaponics system to have a maximum water level set in the grow bed so that it's around 25mm down from the top of the media. This helps prevent evaporation, and also some diseases and fungal attacks associated with the stems of various plants being too wet.
So the jury is still out (for capsicum) as far as using a sprouter for seed raising in aquaponics.
120 Things in 20 years
This might not be a big deal, as it might just coil around a bit until it creates a stand for itself, and then goes about it's growy business.
The danger will be that by the time it creates a stand for itself, it will be out of energy.
As I understand it, the sprout grows only from the energy stored in the seed, and water from the environment. Some seeds need to get through quite a bit of dirt, so I'm hoping nature has left a little in reserve.
I guess they will still grow even if I transplant them as a coil, but I was hoping for a nice straight tap root to make sure it reaches the water in the aquaponics system.
It's normal in an aquaponics system to have a maximum water level set in the grow bed so that it's around 25mm down from the top of the media. This helps prevent evaporation, and also some diseases and fungal attacks associated with the stems of various plants being too wet.
So the jury is still out (for capsicum) as far as using a sprouter for seed raising in aquaponics.
120 Things in 20 years
Thinking - Nutrition
The problem with reality is that you could probably grow a pig to market size on nothing but white rice.
So it would really be made of white rice and every bit of all the goodness within.
I'm guessing the same applies to chickens, cows, fruit, vegetables, air and everything else.
You really need to trust that your food supply isn't governed by anyone with a motive other than providing you with the most nutritious, and healthy food possible.
Now, I'm pretty sure you can trust your local branch of a multinational food retailer to have your best interests at heart rather than, say, some kind of profit motive, but when you grow stuff at home, you actually know that it's not only been raised ethically, and organically, but it's perhaps most importantly, had a decent diet.
I think this applies to all your bodily inputs.
Air, water, fruit, vegetables, meat, fungi, and whatever else you like to stick in your body.
I was recently reading about chicken being a good source of omega three fatty acids, but you have to like reading antique books to get any hint of this. So chicken like your great grandmother used to grow, not chicken you buy now, even when it's branded "organic".
In Australia at least, I think we can trust the organic label, but organic doesn't mean ethical, and organic definitely doesn't mean nutritious. Ethical doesn't mean nutritious either. At least, not by any standard applied here, but perhaps it should.
Organic just means it's not particularly poisonous.
Ethical doesn't relate to the food in any way, but rather speaks to the conditions of the people involved in the production. Worthy indeed, but not anything to do with nutrition.
Every time I crack a store bought (organic, free range) egg I wonder what it is that they replaced the yoke with. Our home grown eggs looked like a sunset, compared to the midday sun of the best eggs I can buy. Bright and sunny, but lacking flavour. Even lacking the second white.
Every egg I cracked when we had chickens had a yoke, a white, and a second, different white.
I've never seen the second white on a store bought egg no matter how much I paid.
I don't know if that second egg white is worth anything. For all I know its some sign of it being toxic. But I suspect its something more to do with the chicken having a decent diet. Our chickens had the daytime run of thirty acres but only really used less than one. They had unlimited access to water, grain and chicken pellets, but much preferred everything else they could find by scratching around, or simply following the pig on his daily digs.
I understand the need for intensive farming in a modern world, but I cant help thinking that the world needs a new movement that is ethical, organic, and also nutritious. We really don't have a "nutritious" standard.
I suspect "nutritious" might even be more important than "organic" or even "ethical", as far as long term health benefits go.
But I also suspect everyone who isn't me is crazy.
so...
I guess it's your call.
But I'm pretty sure I could raise a chicken "organically" and "ethically" to market weight, feeding it nothing but white rice, and I'm pretty sure it wouldn't be very good for you, and it wouldn't be very good for the chicken. I even think the farmer (me in this case) wouldn't feel as good as they could either.
I think we need to protect the word "food", and decide what it means, before a packaging or petroleum company does.
120 Things in 20 years thinks that thinking about nutrition in modern food can make you a little sad, but also thinks that might just be a nutritional deficit causing that feeling.
* There's no reference in the text that might make you look here but I thought it was high time I added a footnote, because it's been a while.
120 Things in 20 years - Aquaponics - Capsicum sprout
The capsicum sprouting is going fine. I think they were originally planted on the 8th of October, and showed first signs of a shoot on the 17th. It's now the 22nd, and the one I've been taking photos of is now starting to concentrate on going up a bit.
It looks like this.
The root is a little longer, but more importantly, it all sits in the wet now. The seed is doing it's best to stand upright, and there is some kind of demarcation between underground stuff, and above ground stuff.
The surface area the roots have is amazing. The photo doesn't really show just how fine the finest roots really are, so you'll just have to trust me.
Amazingly fine.
Big surface area.
The last 20 times or so that I have typed "capsicum", I've typed "cupsicup" instead, and my camera...
Sounds like it's in pain when I turn it on and the lens grinds to a halt.
Then for some reason sounds an alarm at half the volume of the grinding noise, to tell me about all the grinding that's going on.
Then grinds a bit more as it tries an automatic emergency shut-down.
And the takes photo's with nice dark corners.
But it also takes pictures like the capsicum sprout above which I think is pretty good for a low end digital camera, that has taken just short of 5500 pictures, so I guess it's just getting sleepy. Perhaps that's why it does the creepy crocodile eye thing.
120 Things in 20 years wants a new SLR camera, so I can take better photos of my capsicum sprouts for my aquaponics system.
It looks like this.
The root is a little longer, but more importantly, it all sits in the wet now. The seed is doing it's best to stand upright, and there is some kind of demarcation between underground stuff, and above ground stuff.
The surface area the roots have is amazing. The photo doesn't really show just how fine the finest roots really are, so you'll just have to trust me.
Amazingly fine.
Big surface area.
The last 20 times or so that I have typed "capsicum", I've typed "cupsicup" instead, and my camera...
Sounds like it's in pain when I turn it on and the lens grinds to a halt.
Then for some reason sounds an alarm at half the volume of the grinding noise, to tell me about all the grinding that's going on.
Then grinds a bit more as it tries an automatic emergency shut-down.
And the takes photo's with nice dark corners.
But it also takes pictures like the capsicum sprout above which I think is pretty good for a low end digital camera, that has taken just short of 5500 pictures, so I guess it's just getting sleepy. Perhaps that's why it does the creepy crocodile eye thing.
120 Things in 20 years wants a new SLR camera, so I can take better photos of my capsicum sprouts for my aquaponics system.
Aquaponics - Capsicum sprout fuzz
I think it's day three now since I saw the first signs of life in my capsicum seeds I'm attempting to raise in my bean sprout sprouter.
Nature is doing this at the moment.
I think the fuzz is just a root system developing, but it could also just be mould.
My science fu is weak at the moment.
It would be easy enough to research it, but I like a surprise.
I think I'll just keep watching.
120 Things in 20 years - my aquaponics capsicum sprout fuzz comment fu also lacks dynamism today.
Nature is doing this at the moment.
I think the fuzz is just a root system developing, but it could also just be mould.
My science fu is weak at the moment.
It would be easy enough to research it, but I like a surprise.
I think I'll just keep watching.
120 Things in 20 years - my aquaponics capsicum sprout fuzz comment fu also lacks dynamism today.
Aquaponics - Sprouter seed raising
A few of my capsicum (Sweet Romano peppers) seeds have come to life.
I put them into by bean sprout sprouter that I bought a while back.
It seems to have worked.
I also planted some seeds directly in the grow bed to compare, but there is no sign of them doing anything yet. I wouldn't imagine they would sprout any sooner in a grow bed than a bean sprout sprouter, but even if they did I wouldn't see them yet as they are below the surface. I'm trying to avoid the temptation of digging around a bit in the media, because I'd like to keep this as scientific as I can.
It's a little early to call it a success, but I think it will probably work. I think I'll call it a success once it's been successfully transplanted, and even then, it will need to better that simply direct seeding into the grow bed.
What sprouting will enable me to do, is be a bit more accurate in my placement of plants. When you direct seed a bed, you can never tell how many seeds will germinate, and if they will be all nicely spaced out.
120 Things in 20 years sometimes sees posts about raising seed for aquaponics in a sprouter, being marked with the word "success" even when it was just explained that it wasn't really a success.
I put them into by bean sprout sprouter that I bought a while back.
It seems to have worked.
I also planted some seeds directly in the grow bed to compare, but there is no sign of them doing anything yet. I wouldn't imagine they would sprout any sooner in a grow bed than a bean sprout sprouter, but even if they did I wouldn't see them yet as they are below the surface. I'm trying to avoid the temptation of digging around a bit in the media, because I'd like to keep this as scientific as I can.
It's a little early to call it a success, but I think it will probably work. I think I'll call it a success once it's been successfully transplanted, and even then, it will need to better that simply direct seeding into the grow bed.
What sprouting will enable me to do, is be a bit more accurate in my placement of plants. When you direct seed a bed, you can never tell how many seeds will germinate, and if they will be all nicely spaced out.
120 Things in 20 years sometimes sees posts about raising seed for aquaponics in a sprouter, being marked with the word "success" even when it was just explained that it wasn't really a success.
Aquaponics - Tomato dangling
We had some unseasonably cold weather here is South Australia over the last few days, but my grow house seems to be looking after my dangling tomato.
It's two weeks since I put my small collection of small tomato, tomato plants in their small new home.
They looked like this two weeks ago.
The big tall bit in this poorly conceived and poorly executed photo is actually a monster radish plant that has gone to seed. It's growing in the bed behind and below the fishtank.
This group of tomato plants is growing suspended in a plastic container over a fish tank occupied by two silver perch. They sit entirely in air except for the bits that are in water. ie, there is no dirt or gravel or whatever.
They look like this now, two weeks later.
They've grown quite a bit.
The camera is resting on a fixed part of the fish tank, in a known position, so I should be able to get an interesting (to me at least) history of the growth of them over the next 6 months.
I did plan on doing some stop motion photography of some growth but I cant find my old and nearly broken laptop, that is somewhere in the shed. It has such a small hard drive that I wouldn't be able to take many photos, but I have since bought a zillion ziggerbyte backup hard drive that should allow me to run it forever. I just have to find the laptop.
Perhaps its wondered off to go back and sit on the side of the road from whence it originally came.
Anyway, my little tomato experiment must be doing ok, because it's started flowering.
Or that might mean it's stressed.
Lots of things go to seed when they feel the end is nigh.
Sometimes I'm glad humans aren't like lots of things.
It's interesting to watch how fast the roots are growing as well.
They look like this already, and within a week will be able to reach from the centr hole of the IBC where they live, all the way to the front wall.
It's a bit deceiving, because all the roots are swept towards the opening in the fish tank by the current, so there aren't quite as many roots as it looks. Not that you would know how many roots there are because I haven't posted up the photo of them.
I'll do it now.
120 Things in 20 years recently invented "just in time photography" and used it here first, when discussing dangling aquaponics tomatoes.
It's two weeks since I put my small collection of small tomato, tomato plants in their small new home.
They looked like this two weeks ago.
The big tall bit in this poorly conceived and poorly executed photo is actually a monster radish plant that has gone to seed. It's growing in the bed behind and below the fishtank.
This group of tomato plants is growing suspended in a plastic container over a fish tank occupied by two silver perch. They sit entirely in air except for the bits that are in water. ie, there is no dirt or gravel or whatever.
They look like this now, two weeks later.
They've grown quite a bit.
The camera is resting on a fixed part of the fish tank, in a known position, so I should be able to get an interesting (to me at least) history of the growth of them over the next 6 months.
I did plan on doing some stop motion photography of some growth but I cant find my old and nearly broken laptop, that is somewhere in the shed. It has such a small hard drive that I wouldn't be able to take many photos, but I have since bought a zillion ziggerbyte backup hard drive that should allow me to run it forever. I just have to find the laptop.
Perhaps its wondered off to go back and sit on the side of the road from whence it originally came.
Anyway, my little tomato experiment must be doing ok, because it's started flowering.
Or that might mean it's stressed.
Lots of things go to seed when they feel the end is nigh.
Sometimes I'm glad humans aren't like lots of things.
It's interesting to watch how fast the roots are growing as well.
They look like this already, and within a week will be able to reach from the centr hole of the IBC where they live, all the way to the front wall.
It's a bit deceiving, because all the roots are swept towards the opening in the fish tank by the current, so there aren't quite as many roots as it looks. Not that you would know how many roots there are because I haven't posted up the photo of them.
I'll do it now.
120 Things in 20 years recently invented "just in time photography" and used it here first, when discussing dangling aquaponics tomatoes.
Aquaponics - Pest control flooding
One of the excelent by products of growing your vegitables and herbs in water and media filled containers, is your ability to get rid of pests.
Before I replant my grow bed, I flood it for a half hour or so and see what's been living in my media.
Lots of beasties only come out at night, and hide during the heat of the day.
Especially slugs.
Almost impossible to track down in a conventional garden without just dumping poison everywhere, a flooded grow bed quickly brings them all to the surface, and climbing the walls to get to high ground.
Then it's simply a case of collecting them and feeding them to the fish.
I've been thinking of approaches to an aquaponics based snail farm, (I guess Helioponics) and that in turn has me thinking about a growbed that you could flood deep enough to introduce the fish to.
It's also led to some thoughts on snail barriers.
120 Things in 20 years has be thinking about thinking about things
Before I replant my grow bed, I flood it for a half hour or so and see what's been living in my media.
Lots of beasties only come out at night, and hide during the heat of the day.
Especially slugs.
Almost impossible to track down in a conventional garden without just dumping poison everywhere, a flooded grow bed quickly brings them all to the surface, and climbing the walls to get to high ground.
Then it's simply a case of collecting them and feeding them to the fish.
I've been thinking of approaches to an aquaponics based snail farm, (I guess Helioponics) and that in turn has me thinking about a growbed that you could flood deep enough to introduce the fish to.
It's also led to some thoughts on snail barriers.
120 Things in 20 years has be thinking about thinking about things
Fire - Mutton fat burner
There two ways you can stay warm with mutton fat. One is to simply eat it just before bed, get restless leg syndrome as your body tries to figure out what to do with all the fuel in it's bloodstream, and wait until your wife knocks you out with a club, and the other is to burn it in your DIY turbo jet methanol burner.
I chose a combination of both.
I ate a lot of it, but then put a toothpick in the remainder (spooned out of the frying pan) as a wick, and set the rest on fire in my coke can alcohol stove.
It worked a bit.
Nothing like the heat output of using ethanol, but still easily enough to cook a lamb chop from the fat left behind after cooking a lamb chop.
It looked like this with the lights on...
and this with the lights out.
A far cry from the results obtained from the same burner when it was fuelled with pure alcohol, but still plenty of heat to cook a lamb chop - which drops enough fat to cook a lamb chop, which drops enough fat to cook a lamb chop, etc etc
120 Things in 20 years cooks with a fire, fuelled only by mutton fat (and a toothpick wick) from the previous lamb chop, and asks a nearby physicist, "Who said there's no such thing as a free lunch? You've clearly never crashed a wedding reception.".
I chose a combination of both.
I ate a lot of it, but then put a toothpick in the remainder (spooned out of the frying pan) as a wick, and set the rest on fire in my coke can alcohol stove.
It worked a bit.
Nothing like the heat output of using ethanol, but still easily enough to cook a lamb chop from the fat left behind after cooking a lamb chop.
It looked like this with the lights on...
and this with the lights out.
A far cry from the results obtained from the same burner when it was fuelled with pure alcohol, but still plenty of heat to cook a lamb chop - which drops enough fat to cook a lamb chop, which drops enough fat to cook a lamb chop, etc etc
120 Things in 20 years cooks with a fire, fuelled only by mutton fat (and a toothpick wick) from the previous lamb chop, and asks a nearby physicist, "Who said there's no such thing as a free lunch? You've clearly never crashed a wedding reception.".
Aquaponics - Loop siphon
Loop siphons are an interesting beast, so I'm going to have a look at them.
I am currently using either a plastic cup scrunched into the gap that I made too small for a proper siphon, or a small glass jar as a bell in my strawberry grow bed. The strawberries are suffering a bit and they don't look as healthy as the strawberry plants I put in the dirt.
We cant have that.
One of the problems with the scrunched plastic cup and small glass jar,was that they make the water level too low for the strawberry plants. What I needed was a normal every day siphon.
I suspect that people tend toward either bell siphons or loop siphons based on which one they got to work first. Now, I know bell siphons are better, but I don't know why I think that, so I built a proper loop siphon.
One that works.
I started with this pile of junk and leftovers from other projects.
A pile of junk is always a good place to start.
And I made this.
I didn't work.
In fact it's kind of difficult to see in this picture, because there really isn't anything that looks like a loop.
The reason I made it like this is because black poly pipe doesn't like to bend.
I suspect I could have made it work by messing about with the flow for a bit longer, but I thought I should make something a bit more conventional because it was, after all, for a blog post.
So I made one that looked like this instead.
Much better.
And it also worked perfectly the first time without any adjustment
It's still not quite conventional because it looks like this from the top.
Which isn't very loopy.
Anyway, it seems to be quite reliable, and I can see no reason why I wouldn't use another one in some future build.
Except...
for some reason it isn't as interesting as a bell siphon. For one thing it doesn't make any interesting noises. That could be a plus.
So.
It takes 13 and a half minutes to complete a full flood and drain cycle.
When the grow bed is full, it begins at a trickle and stays that way for a round a minute.
This is the view looking down the media guard when the grow bed is full.
After around a minute it triggers convincingly and starts to empty the bed faster than the water is being pumped into the bed (the pump is run continuously).
Then when the grow bed's water level reaches the height of the outlet pipe, it gulps and burps a few times as it sucks in air and then stops after a minute or so of trying.
This is roughly at the 6 and a half minute mark, so half way through the cycle.
One frequent question is "How long should the flood and drain cycle be?", and after lots of reading and personal experiment, I can confidently say it doesn't matter.
But that's not entirely true.
You don't want your media to dry out, because the plants will die. And as far as over watering goes, you don't want plants that don't like to be too wet (I found strawberries and capsicum plants fall into this category).
So as a guide, I'd say anything between ten minutes and an hour and a half should be ok. aim for something in the middle, and don't care if you are a bit off.
As for loop siphons, a few things to remember are...
* don't make your loop too big because the pipe needs to seal with water to become a siphon, and a long gentle curve seems to work better. The longer it is, the less it will trigger in a nice decicive way. It will probably still work, but if your loop siphon is making lots of false starts it might need the loop to be tightened a bit. Mine loop is around 20cm in diameter, which is about as tight as garden hose likes to be bent.
*There is a range of flow at which a siphon will both trigger, and also stop. To make a siphon easy to calibrate, just add a tap to the water going into the grow bed. If it doesn't start, you need more flow. (or reduce the diameter of the loop tube), it it doesn't stop, you need less flow (or increase the size of the loop tube's diameter).
*Remember that if you have more than one grow bed, any adjustment to how much water you direct into one grow bed, will probably effect how much is going to the other.
To get around this you can put a tap on a T junction so that, rather than the tap adjusting how much water goes into the grow bed directly, it adjusts how much water you divert back to the container where the pump is.
This is a good idea for any style of siphon if you have more than one grow bed.
The water that goes back to the sum just adds aeration to the water, so it isn't wasted.
Another use for the diverted water might be to feed a constant flood growbed, where the amount of water can vary without concern.
*It seems that the siphon triggers more decisively when the exit end is pointing straight down. The direction or angle of the entry end of the loop didn't seem to make any difference in my experiments.
My 500ml jug took 11.3 second to fill at the hose bringing water to the grow bed, and 5.1 seconds to fill at the pipe draining water out of the grow bed.
My siphon's loop is made from 12mm (internal) garden hose.
I don't think there is a lot of difference between a bell siphon, and a loop siphon. In future, I'll be using whichever one I feel like making at the time.
The only disadvantage I can think of is that if you were making a very large diameter on, the loop might be difficult to make because big pipe tends to be thick pipe, and think pipe doesn't like to bend. You could probably scale the loop up to any size, but the loop might take up a lot of space. A Bell siphon can be scaled up to any size and not take up a lot of space.
Advantages include that with a loop siphon, you can adjust your water depth in a grow bed simply by repositioning your loop a little higher (the top of the loop sets the grow bed water height), and a loop siphon is probably a bit cheaper to make.
120 Things in 20 years changed it's mind about loop siphons in aquaponics.
I am currently using either a plastic cup scrunched into the gap that I made too small for a proper siphon, or a small glass jar as a bell in my strawberry grow bed. The strawberries are suffering a bit and they don't look as healthy as the strawberry plants I put in the dirt.
We cant have that.
One of the problems with the scrunched plastic cup and small glass jar,was that they make the water level too low for the strawberry plants. What I needed was a normal every day siphon.
I suspect that people tend toward either bell siphons or loop siphons based on which one they got to work first. Now, I know bell siphons are better, but I don't know why I think that, so I built a proper loop siphon.
One that works.
I started with this pile of junk and leftovers from other projects.
A pile of junk is always a good place to start.
And I made this.
I didn't work.
In fact it's kind of difficult to see in this picture, because there really isn't anything that looks like a loop.
The reason I made it like this is because black poly pipe doesn't like to bend.
I suspect I could have made it work by messing about with the flow for a bit longer, but I thought I should make something a bit more conventional because it was, after all, for a blog post.
So I made one that looked like this instead.
Much better.
And it also worked perfectly the first time without any adjustment
It's still not quite conventional because it looks like this from the top.
Which isn't very loopy.
Anyway, it seems to be quite reliable, and I can see no reason why I wouldn't use another one in some future build.
Except...
for some reason it isn't as interesting as a bell siphon. For one thing it doesn't make any interesting noises. That could be a plus.
So.
It takes 13 and a half minutes to complete a full flood and drain cycle.
When the grow bed is full, it begins at a trickle and stays that way for a round a minute.
This is the view looking down the media guard when the grow bed is full.
After around a minute it triggers convincingly and starts to empty the bed faster than the water is being pumped into the bed (the pump is run continuously).
Then when the grow bed's water level reaches the height of the outlet pipe, it gulps and burps a few times as it sucks in air and then stops after a minute or so of trying.
This is roughly at the 6 and a half minute mark, so half way through the cycle.
One frequent question is "How long should the flood and drain cycle be?", and after lots of reading and personal experiment, I can confidently say it doesn't matter.
But that's not entirely true.
You don't want your media to dry out, because the plants will die. And as far as over watering goes, you don't want plants that don't like to be too wet (I found strawberries and capsicum plants fall into this category).
So as a guide, I'd say anything between ten minutes and an hour and a half should be ok. aim for something in the middle, and don't care if you are a bit off.
As for loop siphons, a few things to remember are...
* don't make your loop too big because the pipe needs to seal with water to become a siphon, and a long gentle curve seems to work better. The longer it is, the less it will trigger in a nice decicive way. It will probably still work, but if your loop siphon is making lots of false starts it might need the loop to be tightened a bit. Mine loop is around 20cm in diameter, which is about as tight as garden hose likes to be bent.
*There is a range of flow at which a siphon will both trigger, and also stop. To make a siphon easy to calibrate, just add a tap to the water going into the grow bed. If it doesn't start, you need more flow. (or reduce the diameter of the loop tube), it it doesn't stop, you need less flow (or increase the size of the loop tube's diameter).
*Remember that if you have more than one grow bed, any adjustment to how much water you direct into one grow bed, will probably effect how much is going to the other.
To get around this you can put a tap on a T junction so that, rather than the tap adjusting how much water goes into the grow bed directly, it adjusts how much water you divert back to the container where the pump is.
This is a good idea for any style of siphon if you have more than one grow bed.
The water that goes back to the sum just adds aeration to the water, so it isn't wasted.
Another use for the diverted water might be to feed a constant flood growbed, where the amount of water can vary without concern.
*It seems that the siphon triggers more decisively when the exit end is pointing straight down. The direction or angle of the entry end of the loop didn't seem to make any difference in my experiments.
My 500ml jug took 11.3 second to fill at the hose bringing water to the grow bed, and 5.1 seconds to fill at the pipe draining water out of the grow bed.
My siphon's loop is made from 12mm (internal) garden hose.
I don't think there is a lot of difference between a bell siphon, and a loop siphon. In future, I'll be using whichever one I feel like making at the time.
The only disadvantage I can think of is that if you were making a very large diameter on, the loop might be difficult to make because big pipe tends to be thick pipe, and think pipe doesn't like to bend. You could probably scale the loop up to any size, but the loop might take up a lot of space. A Bell siphon can be scaled up to any size and not take up a lot of space.
Advantages include that with a loop siphon, you can adjust your water depth in a grow bed simply by repositioning your loop a little higher (the top of the loop sets the grow bed water height), and a loop siphon is probably a bit cheaper to make.
120 Things in 20 years changed it's mind about loop siphons in aquaponics.
Aquaponics - Sweet Romano Peppers (capsicum)
If you haven't tried this Sweet Romano Pepper variety of capsicum, you really should.
I just harvested the last of last years crop (it's spring here again) and these managed to stay fresh in the grow house until I picked them today.
Actually they are a bit past their prime (the curved one on the bottom lest has gone a little soft), but they still taste amazing.
Definitely plant this variety.
I even recommend you just go out and buy this variety if you can. I predict this will spell an end to our normal capsicums dominance within a few years.
120 Things in 20 years - Aquaponics - Sweet Romano Peppers (capsicum). I'm off to invest in capsicum futures.
I just harvested the last of last years crop (it's spring here again) and these managed to stay fresh in the grow house until I picked them today.
Actually they are a bit past their prime (the curved one on the bottom lest has gone a little soft), but they still taste amazing.
Definitely plant this variety.
I even recommend you just go out and buy this variety if you can. I predict this will spell an end to our normal capsicums dominance within a few years.
120 Things in 20 years - Aquaponics - Sweet Romano Peppers (capsicum). I'm off to invest in capsicum futures.
Aquaponics - Sprouts
I found a device for making sprouts. Spouts for food. Bean sprouts etc. And I discovered I had to buy it.
It was $20 and consists of 5 layers of dish, each around two inches high, and they are stackable. The bottom container has no siphon, and is there just to catch water.
You sprinkle grain around in one of the trays and then pour water into the top.
The water flows through each chamber in turn, and they all get a rinse and a watering.
The water collects in the bottom and is emptied.
Pictured here is some lentils and beans that I found in the cupboard.
The water flows through a tiny bell siphon.
The siphon looks like this with the bell off.
So you put some seeds in, and a few days later, you get a nich little field of spouts. In this case alf alfa.
But I thought it might make a good way to raise seeds for aquaponics, so that they had a root long enough to get down to the water before being added to the system.
Planting seeds directly is a bit hit and miss in aquaponics. When ever I've done it, the results are a little patchy, I think because some seeds don't fall into the media enough, some too much, and some just right.
So I put some of my favourite variety of capsicum into the tray to see what would happen.
The variety is "Sweet Romano Pepper" and it's the only one worth growing in my opinion.
They are a zillion times sweeter than the more square variety that is the only one that seems to be available here.
I like this product so much I''d sell it to you if I could.
All that's left now is to wait for a bit and see if this seed raising method will work.
That 120 Things in 20 years - Aquaponics - Sprouts post took a while to get to the point.
It was $20 and consists of 5 layers of dish, each around two inches high, and they are stackable. The bottom container has no siphon, and is there just to catch water.
You sprinkle grain around in one of the trays and then pour water into the top.
The water flows through each chamber in turn, and they all get a rinse and a watering.
The water collects in the bottom and is emptied.
Pictured here is some lentils and beans that I found in the cupboard.
The water flows through a tiny bell siphon.
The siphon looks like this with the bell off.
So you put some seeds in, and a few days later, you get a nich little field of spouts. In this case alf alfa.
But I thought it might make a good way to raise seeds for aquaponics, so that they had a root long enough to get down to the water before being added to the system.
Planting seeds directly is a bit hit and miss in aquaponics. When ever I've done it, the results are a little patchy, I think because some seeds don't fall into the media enough, some too much, and some just right.
So I put some of my favourite variety of capsicum into the tray to see what would happen.
The variety is "Sweet Romano Pepper" and it's the only one worth growing in my opinion.
They are a zillion times sweeter than the more square variety that is the only one that seems to be available here.
I like this product so much I''d sell it to you if I could.
All that's left now is to wait for a bit and see if this seed raising method will work.
That 120 Things in 20 years - Aquaponics - Sprouts post took a while to get to the point.
Thinking - Latin
Why is it, that anyone using... Latin... speak... gains a stack of extra argument points in any discussion about nature, but gains nothing in a discussion about hand guns?
Anyone can create an environment where you are seen as an expert if you say something like "Gallus gallus domesticus" when you really mean chicken. ie, "I'll have the Gallus gallus domesticus burger meal deal, hold the Allium cepa.", but the problem with trying to sound informed during a discussion about hand guns, is that when you fall back on this old Latinspeak standard, you quickly run out of words.
I know because I recently tried it*.
I don't actually know Latin, so this made my experence extra bad.
A discussion that goes something like, "A Hmm... is vastly superior to a ...mumble mumble in a liquor store robbery", simply makes you look like an idiot if you try to translate "hand gun" or "AK-47 "into Latin to win prestige points.
That's all I've got to say on that really.
But on a lighter note, did you know that the AK-47 (Автомат Калашникова) features on the Mozambique flag?
And further, did you know that the AK-47 is called the AK-47 because that's when it was designed (or finalized in design) ... in 1947?
A timeless design.
Apparently.
Those are rhetorical questions.
120 Things in 20 years today asks "Is it bed time yet?" instead of the google translation, "Est lectum tempus tamen." (which slightly interestingly translates back to "There is yet time to bed for" which then translates back to "Est enim lectus, tempus", which translates to "There is a bed, a time.", which translates to "Est lectus, tempus." which then seems to settle out and translate the same no matter how many times you run it.)
I just thought you should know that.
*Some facts have been changed in the interest of narrative flow
Anyone can create an environment where you are seen as an expert if you say something like "Gallus gallus domesticus" when you really mean chicken. ie, "I'll have the Gallus gallus domesticus burger meal deal, hold the Allium cepa.", but the problem with trying to sound informed during a discussion about hand guns, is that when you fall back on this old Latinspeak standard, you quickly run out of words.
I know because I recently tried it*.
I don't actually know Latin, so this made my experence extra bad.
A discussion that goes something like, "A Hmm... is vastly superior to a ...mumble mumble in a liquor store robbery", simply makes you look like an idiot if you try to translate "hand gun" or "AK-47 "into Latin to win prestige points.
That's all I've got to say on that really.
But on a lighter note, did you know that the AK-47 (Автомат Калашникова) features on the Mozambique flag?
And further, did you know that the AK-47 is called the AK-47 because that's when it was designed (or finalized in design) ... in 1947?
A timeless design.
Apparently.
Those are rhetorical questions.
120 Things in 20 years today asks "Is it bed time yet?" instead of the google translation, "Est lectum tempus tamen." (which slightly interestingly translates back to "There is yet time to bed for" which then translates back to "Est enim lectus, tempus", which translates to "There is a bed, a time.", which translates to "Est lectus, tempus." which then seems to settle out and translate the same no matter how many times you run it.)
I just thought you should know that.
*Some facts have been changed in the interest of narrative flow
Aquaponics - Carrot haul
I pulled up the last of my aquaponics carrot patch and was pleasantly surprised by the result.
I suspect I could have planted them a lot closer together, but I harvested enough that I think it's a worthwhile crop for aquaponics.
Generally speaking, I try to grow quick growing or repeat harvest produce because I have such a limited space, but I might be able to grow carrots under my capsicum plants or something.
One of the issues with growing things like carrots or potatoes is that when they are in season in your garden, they are practically free at the supermarket, but these carrots had quite a long season where I could pick them a bit young, or a bit old. Either way they tasted good, and it was nice to have perfectly fresh carrot kicking around.
All in all, I would say carrots were a success in aquaponics.
I suspect I could have planted them a lot closer together, but I harvested enough that I think it's a worthwhile crop for aquaponics.
Generally speaking, I try to grow quick growing or repeat harvest produce because I have such a limited space, but I might be able to grow carrots under my capsicum plants or something.
One of the issues with growing things like carrots or potatoes is that when they are in season in your garden, they are practically free at the supermarket, but these carrots had quite a long season where I could pick them a bit young, or a bit old. Either way they tasted good, and it was nice to have perfectly fresh carrot kicking around.
All in all, I would say carrots were a success in aquaponics.
Aquaponics - Dangling tomato
Originally I put a cutting from last years tomato into the fishtank in the hope that it would take root, and become my new tomato plant for this year, but for some reason it didn't and decided it would rather die.
Normally that doesn't happen.
I bought a punnet of cherry tomatoes and washed all the dirt from the roots.
Then I found this food container, and drilled it full of holes.
I teased the tomato roots through some of the holes, until it looked a bit like this.
An easy way to get the roots through is to run water through it. The water collects the roots on the way through.
Then I sat the new pot plant over the large screw top lid hole in the centre of the IBC.
The roots just touch the water, and the others should find their own way in the near future.
If it works, the root mass will be able to take up as much of the fish tank as it wants. I suspect the fish will enjoy it, and it might offer any young ones I add a bit of cover.
It looks like this with the camera nearly under water, looking under the plastic at the roots.
That's the reflection of the underside of the hole in the IBC with the pot plant and roots, not some crazy vortex.
That string you can see coming down from top of frame, is just a piece of string.
I guess this is an example of deep water culture.
120 Things in 20 years is probably going to have an aquaponics dangling tomato free year.
Normally that doesn't happen.
I bought a punnet of cherry tomatoes and washed all the dirt from the roots.
Then I found this food container, and drilled it full of holes.
I teased the tomato roots through some of the holes, until it looked a bit like this.
An easy way to get the roots through is to run water through it. The water collects the roots on the way through.
Then I sat the new pot plant over the large screw top lid hole in the centre of the IBC.
The roots just touch the water, and the others should find their own way in the near future.
If it works, the root mass will be able to take up as much of the fish tank as it wants. I suspect the fish will enjoy it, and it might offer any young ones I add a bit of cover.
It looks like this with the camera nearly under water, looking under the plastic at the roots.
That's the reflection of the underside of the hole in the IBC with the pot plant and roots, not some crazy vortex.
That string you can see coming down from top of frame, is just a piece of string.
I guess this is an example of deep water culture.
120 Things in 20 years is probably going to have an aquaponics dangling tomato free year.
Aquaponics - Worms
I've been growing a tomato plant for over a year (I think) now, and it's been looking very tired over winter. It was originally in my grow bed with a bell siphon, but at the end of the season I decided I'd pull it up, that was six months ago. In the interim, it's been sitting in a bucket under the input flow to that same growbed, and as far as I knew there was no media for it to grow in, just a stack of roots in a bucket with a drain hole half way up the side.
It looks like this now.
It's seen better days.
It's not quite as dead as it looked, and there are still a few patches of life in various places, but it's definitely time to retire it.
It had quite a bit more green on it only a few days ago, but I cut all the healthy bits off in an attempt to get them to strike roots by sitting them in the fish tank. There's even a few tomatoes.
For some reason it didnt work, even though normally it does. Rather than striking roots, the shoots just all died off.
But when I had a look in the bucket it was living in I found there was actually some media in the bottom. Around a quarter of a 10L bucket of scoria.
But interestingly, I also found these.
Pictured herein what apears to me to be zero gravity are a large handful of some of the most insanely lively worms you ever did see.
All living entirely under water for ever.
I accidentally left them in the water I had them in to take this photo, and within only a few minutes, they had turned from the liveliest bunch of worms to a very sleepy bunch of worms that I'm guessing were not enjoying living in the still water without the dissolved oxygen levels they had enjoyed before.
I think I found them just in time, and have put them into a container with some rotting vegetation to become the first inhabitants of my worm farm. They took nearly five minutes to dig themselves into the ground whereas when I was trying to get them out of the scoria, I sometimes chased a single one for what seemed like five minutes.
It seems worms like to breath.
120 Things in 20 years - Discovering the obvious about Aquaponics and worms.
It looks like this now.
It's seen better days.
It's not quite as dead as it looked, and there are still a few patches of life in various places, but it's definitely time to retire it.
It had quite a bit more green on it only a few days ago, but I cut all the healthy bits off in an attempt to get them to strike roots by sitting them in the fish tank. There's even a few tomatoes.
For some reason it didnt work, even though normally it does. Rather than striking roots, the shoots just all died off.
But when I had a look in the bucket it was living in I found there was actually some media in the bottom. Around a quarter of a 10L bucket of scoria.
But interestingly, I also found these.
Pictured herein what apears to me to be zero gravity are a large handful of some of the most insanely lively worms you ever did see.
All living entirely under water for ever.
I accidentally left them in the water I had them in to take this photo, and within only a few minutes, they had turned from the liveliest bunch of worms to a very sleepy bunch of worms that I'm guessing were not enjoying living in the still water without the dissolved oxygen levels they had enjoyed before.
I think I found them just in time, and have put them into a container with some rotting vegetation to become the first inhabitants of my worm farm. They took nearly five minutes to dig themselves into the ground whereas when I was trying to get them out of the scoria, I sometimes chased a single one for what seemed like five minutes.
It seems worms like to breath.
120 Things in 20 years - Discovering the obvious about Aquaponics and worms.
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