Thinking - Three

I was hanging out with a three year old, and a pair of hand held UHF radios the other day.

I said, "You have to push the button and hold it down when you talk.".

She pressed the button briefly, then lowered the radio almost to the ground before she spoke.

Kids are smarter than grownups.

Electronics - Reasonable success milestone

What's pink and white, and looks a bit like a short alien under stage lighting, talking to a tall man with a diode for an upper leg, and a friend with a paper bag over his head?


Too much Christmas spirit.

120 Things in 20 years - Electronics - Demand feeder diorama 

120 Things in 20 years - As at 2012 12 24 23:56 my demand feeder actually works (if you include a light where a motor should be as "working" (which I do)). I declare this point in time , an Official reasonable electronics success milestone.

Electronics - Aquaponics - Motor woes

I found out what was wrong with my motor.

I'll start that again.

I've been having trouble with my motor.

I opened it up and found what the problem is.

Too many parts inside just rattling around doing nothing.

I'm trying to explain to them that everyone has to pull their weight, otherwise nothing gets done.

So far they are ignoring me.

It's hard to fix something when you have no idea what it looked like before it was broken. Firstly, the bit of metal on the end of the yellow wire has to fit through a hole that's half the size of the bit of metal. But it did just fall out through that hole.

Clearly someone's being funny.

There are two bent bits or copper that look like they make contact with the shaft, but I cant see how they could without wearing out, But then, they are actually worn, or at least they look worn. but if there are magnets on the outside that don't have power going to them, and a rotating shaft with copper coils that gets it's power through these copper bits, why not just build the thing inside out, with the coils on the outside, stationary bit, and the fixed magnets on the inside. That way you would avoid the need to put power through a rotating shaft.

I must be missing something 

120 Things in 20 years - Electronic and Aquaponic motor woes, and much of the world, are confusing.

Electronics - Aquaponics - Demand feeder 2 breadboard

I've started work on the electronics and programming of my new demand feeder.

I also found my cardboard fish from the first version demo on youtube, so I thought I'd re-make the video with the new chip and this time, a counter that flashes the number of illegal attempts to get food. There will be another counter to flash feeds and a few others.

But for now, here is where I'm at so far....

I'm feeling a lot more confident this time with a little better understanding of the electronics involved.

120 Things in 20 years - I'd better get back to my Electronics - Aquaponics - Demand feeder 2 breadboard

Electronics - Aquaponics - Demand feeder version 2 schematic

I've been busy.

I've been busy learning how to create a plan, and a circuit schematic to go with the plan.

It looks like this, and I think it might be finished.

I now know a stack of stuff that I didn't before.

Things like...

It's ok to not connect up the earth (0 volt) wires in a schematic.

You just label them as earths, and leave them hanging in the wind.

It actually makes the diagram a look a lot better to read. (thanks SuperVeg)

When you make a real version, all those earths, are connected to the power supply's negative terminal.

So now that I have a plan and a circuit diagram, my next step will be to build a working model on a breadboard, then solder the real thing together.

I've already started.

I've also started to write some of the required software.

120 Things in 20 years - It's 3am

Thinking - Electronics - Education

I'd like to take this self created opportunity, to comment on my experience of the South Australian education system.

It was really, really boring.

For example, the following two phenomena would have got me very interested in science, but were conspicuously absent.

Did you know that if you stick a powerful magnet on a battery, then reach a copper wire so that it balances on a point at the top, and just slightly touches the magnet on the bottom, the device creates a stack of rotational motion?

I didn't, and I've been to school.

It looks like this...

And if you add that failure to educate me to this other example, you see why I'm a little disappointed...

In this second video, the rare earth magnet creates a magnetic field in the copper pipe, and that reacts with the magnet using ordinary magic.

 Both videos are real, but totally lacking in my childhood experience. 

Not happy.

120 Things in 20 years - When thinking about electronics, and education, I want my money back. 

Electronics - Aquaponics - Aquaponics manager

I'm trying again.

I'm making a digital demand feeder, and I have a few other ideas I'd like to try as well.

I'm using a PICAXE 20M2 chip, And I've managed to get as far as this...

Clicking on the image should make it larger.

If anyone is willing, can you please check my layout to make sure I limit how many chips I toast before I actually start toasting them.

This is the serial data connection from the stereo plug to the chip.

The overlay is what it should look like, the rest is my interpretation.

For people that don't know this stuff, the serial data connection is the bit that makes it possible for me to send information from my computer to the chip.

I write code  (computer programming stuff) on my computer on some software provided free by the PICAXE company. When I'm happy with my code I send it to the computer chip (the grey thing that's centre right with all the legs) via a cable that has a USB plug on one end, and a stereo headphone jack on the other. The headphone jack plugs into my project, and the USB end plugs into my computer.

Once you connect the power supply, the chip starts running it's program, and that program typically loops around forever, waiting for external inputs from things like switches, variations in connected voltages, or fish bumping levers.

When the chip detects inputs, it can react according to the code you have written, and produce outputs. (like when your computer displays a box with buttons marked "OK" and "Cancel" , That box is an output, if you click one of the buttons, that becomes an input.

So the code might look something like this...

read this line over and over, unless the fish pushes the lever,  then run the rest of the code

       power up the feeder motor for 3 seconds

       count to a few billion to wait a while so the fish dont get too much feed

go back to the first line

That's roughly what code looks like, but unfortunately computers don't understand English very well, so you have to use very structured language, and code words to make it all work. I wont go into that here.

Here's another bit that connects the lever that the fish will push when they want food...

This time the overlay shows the circuit diagram of a switch and it's connection to the chip.

I'll use a momentary contact switch that is only on when there is pressure on the switch, and reverts to it's natural state - off, when there is no pressure on the switch.

I'll attach a lever that extends down into the fish tank so the fish can press it.

When the fish press the lever they send an input to the chip that sets the code in motion. The code does some calculations and checks to make sure the fish aren't being too greedy, and if all is well, the chip turns the motor on for a few seconds.

The motor section looks like this (I think)...

One form of the chips input and output abilities, is to set the pins "high" or "low". That being high voltage (up to 5 volts) and low voltage down to not very much.

The chip can also receive high and low voltages as inputs.

So we design the circuit so that flipping the switch changes the input from either high to low, or low to high, and then write code that uses the different state to start some other bit of code. The other bit of code might change a different pin from low to high, and trigger the motor.

That code might look something like this...

keep looping this line until the pin the switch is connected to changes from low to high, then...

       check that the fish haven't had too many feeds so far today      

        if they have had too many feeds go back to the first line, otherwise keep going to the next line

       set the pin to which the motor is connected to high, to send power to the motor.

       add one to the number of feeds so far today

Go back to the start

The computer you are sitting at is essentially just a really, really, really complicated version of that.

The chip I'm using works faster than my first desktop computer, and only costs a few dollars.

Please give some feedback on the design if you are familiar with this electronics caper, as I'm still a bit vague on all this stuff. My greatest problems are around interpreting a circuit diagram onto the breadboard with special regard to shared nodes, where say in that last picture all three components meet at that one point. When I place components on the board, they rarely fall in the same layout due to space restrictions etc. Even the fact that the strip board often creates the need for zig zags rather than straight lines. ie three components in a straight line might need to be stepped with each component and wire on a different horizontal line. This can really mess with my head at times. Another problem I have is with missing track cuts that cause shorts.

I also have many other problems with stuff.

I'm not sure I believe in electricity.

So please help me through this part if you can.  There's a comments section under this post, or you can get involved here at Backyard Aquaponics. The project is all open source, and the details of the code, the electronics, and the PVC construction will all be freely available on this blog and at that link.

120 Things in 20 years re-bites off more than it can chew with  an electronic, aquaponics manager.

Photography - Time lapse camera

Someone nice gave me a new camera today.

Thanks someone nice.

It does time lapse photography.

You set it to take a shot every 30 seconds or whatever (30 seconds to 990 minutes), and when you feel like it, you turn it off pull out the memory card, and knit them all together with some software * so you have a movie.

It looks like this.

I've played around with it a bit, and so far the results are excellent.

It was given to me, so I have no idea how much it cost, but they tend to be called "garden cams". A search for "garden cam" will see you on the right track.

With a name like that, clearly they want me to film some aquaponics growth.

Mine is made in china and the box is labelled "Live Cam".  If you do a search for "Live Cam", you get a list of every porn site in the world.

I cant endorse it, or any of the garden cam things mentioned, because I dont know how much mine cost, I haven't used any others, and I never said I would, but I'm pretty stoked at having one to play with. From the size of the jpg's it makes, It's around a three mega pixel camera, so it should make for a reasonably decent film. It's not going to be Imax or anything, but it should be a few million times better than your average liquor store hold up security camera footage.

I suspect it will end up pointing aft, mounted on the back of my little boat for the duration of my planned, epic Murray River adventure.

I've really got to get to work on that boat.

Anyway, this version has a micro SD card slot which means it can hold up to 32 gig of pictures. I just worked out how many 4 meg photo's that is, but I closed the calculator without looking at the result, and I never go back.


You'll have to work that out for yourselves.

It should hold a day's worth, and hopefully the batteries will also last a day at least. I suspect the camera goes into a sleep mode (otherwise the 990 minute setting would be a little pointless) where it doesn't draw a lot of power, but I'll be taking my trusty laptop (that was ripped from the jaws of landfill, and must be 20 years old), so charging (via USB) and emptying the memory shouldn't be an issue. Although, come to think of it, I think the new camera has more memory than the old laptop.

I'll work something out.

On a side note, and interestingly, you can drag a photo of a product into a web page showing google images, and it will search the net for images that match. I recently used it to find all the different labels that my new tent is manufactured under to see how much I got ripped off. (turns out I didn't)

But generally speaking it's a good thing to do before you buy rather than after to see if you got ripped off.

So, if you want to buy a toaster that burns tomorrows weather forecast into your toast, the same device might be marketed under three different labels, at three different price points. The exact same device, made in the same factory, not some kind of poorer quality knockoff.

It's a crazy, crazy world in which we live.

So get the photo, and save it to your desktop, then open google search, then click "images". ie go to google image search. Now grab your pic from the desktop, or another browser tab (you don't have to save it to your desktop (in chrome at least), and drag it into google image search.

It will find all the other versions and brands of your product that are using the same, or similar promotional pics.

Try it with the next product you buy, and depending on where you shop, you may be pleasantly surprised, or utterly disgusted with the universe at large.

You can also try it with a person's image, but it might make you sad. Most peoples's secret lives are very, very, boring.

Stupid universe.

*I use OpenShot Video Editor - a free, open-source video editor for Linux licensed under the GPL version 3.0

120 Things in 20 years - Photography - Time lapse camera. We humans are just like ants, but with no sense of humour.

The beer traps killed quite a few slugs, but it's clear many of the new hatch-lings found my sprouts before they found the traps. I guess that's the problem when they are hatching in the middle of the growbed.

All but three were taken off had their leaves chewed off, leaving just a stem.

I dont like slugs much at the moment.

So now I'm forced to go back to raising seeds in something a bit more like dirt.

This stuff comes in thin, hard, disks.

I think it's peat.

You put them into a tray, and pour some warm water on them.

They look like this when they are half expanded.

They must be poured into a bag, and then compressed, because the bag seems to unfold as the fibre expands.

The bag is thin like rice paper.

It might be rice paper.

I dropped two Sweet Remano pepper seeds into each one.

At first I thought I'd thin each pot out to one seedling by choosing the stronger ones, but now I think I'll just leave them if both grow.

I love this variety so much, that I'm going to grow as many as I can.

I should be able to crowd them in a bit as they have fairly sparse foliage, so ventilation and mould etc shouldn't be a problem.

The grow media looks like this when they are full expanded.

The device has a lid.

It was given to me by my sister in (common) law.

Even if this works well, I'm going to miss out on a lot of capsicums. One of the two plants I have that stayed alive from last summer already have full size* green fruit. That's the variety I dont like so much. The second of the two plants is my favourite sweet remano variety. It doesn't yet have fruit, but has the beginnings of a few flowers.

*for the miniature variety that it is

120 Things in 20 years - Thinks watching peat expand in rice paper bags is... Slightly interesting.

Aquaponics - Sweet Remano Peppers

I raised the rest of my precious stash of Sweet Remano Pepper seeds in the sprouter over the last few weeks, and this time I've been laying beer traps all over their growbed space.

Beer is a wonderful, delicious thing, and an excellent use of grain. But it's even more attractive, and poisonous to slugs and snails as it is to humans.

A snail and slug beer trap is a relatively environmentally friendly way to kill slugs and snails, and involves putting a little beer in a bowl or cup, and leaving in the area you are trying to protect. I use Chinese tea cups. The slugs and snails love the stuff, and either drown in it, or it's poisonous to them in some way. Either way, you find them dead in the traps the next day.

I put four traps out for the last few days leading u to the time I figured I would be transplanting my sprouts, and trapped a few the first day, and none since then. The beer was changed every night at sundown (slugs become active at night) because the alcohol evaporates. I'm not sure if the alcohol has anything to do with it, but I'm guessing it does.

So I diligently maintained the traps before the transplanting, and last night I planted twelve of the sprouts into half of my scoria filled, flood and drain growbed, and another ten or so in a clump in the clay ball filled flood and drain growbed. The ten in the clump were planted like that so I can find space for them later, or fill the gaps from any that don't survive in the bed where they are nicely spaced.

I'll keep up the baiting until my beer runs out.

120 Things in 20 years - Aquaponics - Sweet Remano Peppers - One for the slugs, one for me. One for the slugs, one for me.

Aquaponics - PVC Tube tomatoes

My PVC tube tomato now seems to be growing at full speed.

There's stacks of new growth every day, and the first of the tomato flowers are just starting to form.

That should really read "the first of the tomato flowers since I cut all the existing flowers and leaves off, so that I could jam it into a PVC tube, are just starting to form".

The entire point of the exercise was to get the tomatoes outside where it could grow as big as it wanted without taking up all the space inside, but it looks like the entire system is about to be outside.

The grow house isn't UV stable, and as a result is turning to dust every time I so much as look at it.

Even a sly sideways glance from a distance sees yet more daylight induced destruction.

The hardware chain I bought it from will probably replace it, but this is my third one from them and I'm starting to wonder if they really care about the percentage of my life I spend dealing with a product that really shouldn't give any problems.

Any % of life spent at a returns counter, is too much %.

Aquaponics - Sprouts

It turns out leaving the sprouts in the sprouter for way to long is counter productive.

Who knew.

They went soggy and the leaves fell off.

So I have only one cucumber, (or perhaps it's a rock melon) seedling planted out into the growbed.

I put the last of my Sweet Remano Peppers in the sprouter a few days ago, so they have all sprouted.

I'll be watching them closely to make sure I plant them before they also succumb to my bog inducing delinquence.

Aquaponics - PVC Tube tomato

My PVC tube tomato seems to have found it's feet.

It took a while after I removed all but four or so leaves on each of the four plants that make up this particular experiment.

 It's probably back to around what it looked like four weeks ago.

By my standards, that actually constitutes success.

On a side note, the foliage in the background is the grow bed that I emptied and flooded around five weeks ago (flooded to get any slugs out).

That's lettuce you can see, and we've been cutting a salad a day from just that right hand side. The left hand side was Bok Choy, but that all went to seed, and has since been fed to my worms.

When I put the seedlings in (bought from a shop) I also sprinkled some mixed lettuce seeds around.

It looks like this five weeks later.

We've been harvesting from the front, and you can see some of the seedlings from the seeds are looking a little weak because they have been struggling for light, but now they have some, they will spring to life.

In summer, and harvesting a light lunch size salad each day, (in Adelaide South Australia at least) we found you need around half a blue barrel worth of growbed real estate, as long as you seed every week.

I like coz lettuce because it can be harvested as it grows (ie just cutting off leaves rather than pulling up the plant) , but these loose leaf varieties are proving to be quick growing, and can also be repeat harvested. if you drop seeds in around the seedlings when the seedlings are around the size you buy them at, the seeds are seedlings when the lettuce has been repeat harvested as much as it can, and finally gets pulled out.  I just read that again, and I think all that means something. 

The leaves get bitter toward the end of the lettuce life cycle as they are about to go to seed. The leaves  also grow further apart. So once they start growing from a stalk rather than from a central point at the base, it's time to pull the plant up, and let the light in to the little ones, that are by this time the size of the store bought seedlings.

I don't think I've ever grown the iceberg style lettuce that grows like a cabbage, so I don't know if you can repeat harvest that, but I suspect not. 

I used to take a lot of care with growing lettuce seedlings, and transplanting them, but now all I do is put a stack of different seeds into a jar, and sprinkle a pinch of them around directly into the growbed. 

I suspect the clay balls are better than scoria when you direct seed. I think the seed (especially small seeds like lettuce) fall down until they stick to the side of the media once it's deep enough that the media is damp. 

I suspect that's just right as far ar growing goes. 

Perhaps with scoria, the seeds catch in the holes in the media before they get to the correct depth. 

Or it could just be luck, but I'm seeing much better germination rates in the clay ball media. 

But it's also a constant flood grow bed, so perhaps that's got something to do with it as well. 

120 Things in 20 years - Results, but no science to back it. Oh, and also PVC Aquaponics tomatoes.

Electronics - Aquaponics management system

I've decided to remake my demand feeder from scratch.

I just couldn't figure out what was wrong with existing model, and it may well be because there were just some random bits soldered on. Some stuff didn't seem to serve any function.

So I thought I'd start with some proper documentation and some kind of plan. That way I can work out which chip I need, depending on what functionality I require, and also some plan for expansion.

I also plan on making it work as a demand feeder before making it do anything else like regulate how much feed the fish can have. At the moment my fish can have as much as they want, because I have much more filtration system that I need to cope with only two fish.

The plan looks like this at the moment.

I just started.

I realise that isn't very informative as far as pictures go, but it does in some small way, indicate just how much more I have to do.

120 Things in 20 years - I'm exhausted already just thinking about thinking about the plan on how to make an electronics based aquaponics management system.

Aquaponics - New system bits

I got this.

Which is a 500L grow bed.

And looks like this from the inside.

And I got this.

Which is a 500 litre bucket.

And a stack of bags of this.

Which is around 500L of expanded clay ball grow media.

And now I need to figure out what to do with it.

I was giving some serious thought to getting rid of my aquaponics system, because we need the space for a business venture, and there really isn't anywhere else it (the aquaponics or the business venture) can go.

So I bought all this extra stuff.

This will take my grow bed, and thus filtration capacity up from around 300L to more like 800L

And depending on what I do with the gigantic bucket, I might fill that with media as well and take the capacity up to 1300L

That would mean I could actually have enough fish that it would impact on my diet.

Which is nice.

120 Things in 20 years - Busy with new aquaponics system bits.

Aquaponics - Tomato in PVC

It's been a while since I used PVC in a novel way, so I thought I'd cut all the leaves off my tomato and ram the stems and roots into a PVC pipe.

It seems to have worked.

I like to think of it as a solution.

I started with four tomato plants that have been happily growing with their roots just dangling in my fish tank.

That's them after I fulled them from their comfortable home and lay them on top of the fish tank. They are around a metre long from root tip to top.

They look healthy, and have a stack of clusters of flowers and little fruit forming all over the place.

They were a bit bushy to fit them into a PVC tube with a 90 degree angle and it was going to be way too difficult to jam all that foliage through the pipe, so I trimmed some of it away.


Now it fit easily into the pipe so that the tips were peeking out of one end, and the roots hanging out of the other.

The only thing now is to see if my aquaponics system will be a nice enough place for it to live that it bounces back from my cutty mistreatment.

I'm willing to bet this experiment will work quite well.

One potential problem I can see is that it will still try to make foliage in the pipe, and as a result, the conditions in the Tube will be damp and still, and that might lead to disease.

If that looks like being the case, I can always simply cut the PVC away with scissors.

It only has to last long enough for the tomatoes to reach outside and concentrate their growing out there.

Once there is enough foliage outside, and if I do have to cut the PVC away, it should be easy enough to keep the stems inside the grow house free of new growth.

120 Things in 20 years - only time will tell if my aquaponics PVC tomato works. It should be just a few weeks before I know.

Aquaponics - Cucumber sprouts

Every single one of the capsicum sprouts got munched by slugs.

Now I have cucumber sprouts that have worked realy well in the bean sprout sprouter.

These seem to have done particularly well in the sprouter, but that could just be because they are a large seed, and make a large sprout.

I'm calling using a bean sprout sprouter to raise seedlings for aquaponics, a total success.

This cucumber sprout is around 240mm in total length from tip of root to leaves.

That's a big sprout.

All grown from seed in the bean sprout sprouter, and all strong, healthy, and best of all totally organic.

Actually the real "best of all", is that it doesnt contain any dirt that needs washing off before planting in the system.

Also, it's length means the roots should reach nearly to the bottom of my grow beds.

Much more than they need to find all the water and nutrient they could desire.

And all that means they should have no problems growing.

120 Things in 20 years - struggling without a spell checker to post anything at all, but still managing to put some semi-science out there in the form of my Aquaponics cucumber sprouts.

Aquaponics - Fish stocking density


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.


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.


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.


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.

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.


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.

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...



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

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.


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.

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.

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.

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.

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

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.".

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.


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.


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.

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