Aquaponics - Roots in the media

It's quite possible that this is one of those things that everyone does, but it's so obvious that nobody mentions it.

Perhaps everything is one of those things, but I'd rather hear something twice than never know about it, so I'll say it anyway.

For some time, I've been harvesting things like lettuce, then spending valuable seconds of my life getting the media out of the roots and retuning it to the grow beds. Clay balls get loose a bit more readily than scoria, but roots seem determined to hang onto whatever media they find themselves in.

Don't get me wrong, this is no way an issue because it really is only a few seconds, but I'd rather spend those few irreplaceable seconds doing more important things - eating strawberries, looking at fish, that sort of thing.

But I discovered that if you just snap off the roots and leave them in a bucket, the media falls out all by itself.

Bam! Earth shattering tip right there.

I add an extra step for the worms.

When I pull up a lettuce, the root ball always has a few worms in it. Even in the constant flood grow bed there are worms everywhere. And as much as I'm happy to feed my worms to the fish, I like my worms and like it when they live in my growbed rather than die on the ground. So when I snap off the roots, I lay the ball of roots, and media back on the growbed until the next time I wander past. This allows the worms time to get back into the growbed as their root ball home slowly dries.

The next day (or whenever) I drop the root ball into my root ball bucket, where it dries out and leaves the media behind. After the bucket has seen a few root balls added, or when I get around to it, I return the loose media back to the grow bed, and the dried roots and stems to the compost heap. Once in the compost heap, they sit for eternity. We don't use the stuff.



120 Things in 20 years - Wasting compost from the roots caught up in my aquaponics media.

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 - Ground level adjustment

As with some low lying pacific islands, from time to time, it's a good idea to make the ground a bit thicker.

It helps stop everything from dying, and makes everyone feel a little safer.

There has been a lot of settling out of the media in my grow bed over the last year and half, so we decided to finally get around to topping it up.

It will add some extra filtration, and also some extra space for root systems that are now getting huge.

When I dig anywhere in the bed now, I find tomato roots.

I had to lift the celery, and the capsicum (pepper?) plant to stop their stems from rotting, but left the tomato where it was. I understand you can bury a bit of tomato stem, and it will do the right thing and just send down some extra roots and keep on growing.

I'm counting on my two tomato plants to stick to that understanding, as they are currently the main feature of my system.

My computer decided that it didn't want to share any more, so there will be no photo's until it comes around to my way of thinking. In fact there might not be any more blog until it comes around to my way of thinking, or gets itself replaced.


120 Things in 20 years, just Aquaponics - Ground level adjustment

Aquaponics - Settled media

As I mentioned in this post on moss growing on my media, my grow beds seemed to have settled since the move, and are perhaps getting too wet at the surface as a result.

I think it's officially causing problems.

At one stage my media was up near the rim of my blue barrel, but now it sits here.

That's around 100-120mm down from the top, so I can easily fit another bag of scoria on top. This would increase my filtration a bit as well as keeping the surface a bit dryer.

My media is still getting wet on the surface in spite of my trimming the stand pipe by around 15mm. I trimmed it a few weeks ago, but either it wasn't enough, or perhaps the moisture is coming down in the form of grow house rain, rather than up from the bottom, via the pump.

The media that is wet, is the stuff that tends to sit a bit lower than the surrounding media, but it could still be from "rain", and is simply not drying as quickly as the higher sections. I'm only talking about 10mm between the high and low sections.

One down side is that just as my first strawberry was starting to ripen...

It also started to rot where it was touching the damp scoria.

I really wanted to eat that strawberry.

Aquaponics - Core sampler

Last night I had an idea.

I thought it might be nice to be able to see inside my aquaponics system.

I thought I should build some way to take a core sample.

I started with what used to be a aquaponics media screen, and then became a cheese press. Its now a media screen again.

I then created something similar from a thinner length of PVC, and stuck a lid full of holes on the bottom, to form a cup.

This will hold my removable, and replaceable core sample.

The plan is to push the media screen into the media, empty the media from inside the screen, and then sit the core sample cup inside.

It takes a bit of work, but I found it helped to screw the media screen in a bit. It turns out, there is a lot of friction between scoria, and a PVC media screen.

As I drilled the screen down, I removed more and more of the media from inside.

Due to the curved bottom of the blue barrel, it ended up on a bit of an angle, but I think it should work just fine.

I decided to put this contraption under my water inlet so I could have a look at the state of any solids build up.

The system is a year old now so is starting to show signs of maturity. When you dig into it, there is a faint scent of rich healthy soil. Like fresh mushrooms have.



Delicious!

I should be able to take the core out, dump it into a bowl, and see what state the system is in.

I'm not even sure if I'll learn anything by doing this, but it was another opportunity to drill holes in PVC so I couldn't see any harm in making one.








I plan on introducing some worms to my system, so hopefully this will enable me to see where my worms are at as well.

Now all that's left to do is sit back and soak up all the excitement that only a replaceable core sampler can provide.

[edit from the future - opening my first mature core sample]

Aquaponics - Moss

I noticed some moss growing on my scoria today.

I don't know what that means.

It's been raining quite a bit so it might just be rain, but if its not its a bit of a concern.

Its possible that there was a bit of settling of the scoria when I moved houses (perhaps cornflake manufacturers aren't lying to me after all). This might mean the water level is now coming too close to the surface of the growing media.

The water level is set by the standpipe in the bell siphon, so its the same as it always has been, but the lowering of the media means the plants are now also lower.

The plants are looking fine at the moment, and we have already started to harvest salads from the lettuce (we repeat havest leaves from coz lettuce until the plants get too ratty and then replace them). The baby spinach is not quite ready for a similar attack, but soon will be.

I have no idea if higher water levels will cause any problems, but it's normally agreed that the water should only come to within a few centimetres of the top of the media. Plants tend not to like it when they get too wet.


I'll keep a close eye on it and in needs be add some extra media or shave off some height on the standpipe. My plan would be to add media and then gently pull up the plants to a new level. I have no idea if this will work but these things have to be tried :)

So far I've found aquaponics to be very accommodating and gentle to the plants whenever I've transplanted them, or even lifted them out to look at their roots.

Aquaponics - Pump-less cycling Success!

Sometimes, I know things like cycling a pile of gravel should work, but I'm still surprised when they actually do.

After shovelling 3/4 of the gravel into my grow bed, I got lazy and went to bed. But I thought I'd try getting a head start to cycling up my system as gravel in a grow bed, and a pile of gravel on the ground. 

It was about to rain, so I figured it was a good time to add some fish emulsion to the gravel. When I last wrote about pump-less cycling, I promised I'd let you know if it worked.

It worked!

My recent test showed some nitrites.

The sample pictured was taken from rain runoff, at the standpipe in my new growbed.

To make sure I wasn't getting the nitrites from the bottle of fish emulsion, I tested some fresh water with fish emulsion added. 

ammonia 2.0

nitrite 0.0

nitrate 0.0

What this means is, there were no nitrites introduced directly from the bottle of fish emulsion. What that means is that my pump-less, sump-less, no fishtanked system is cycling, because the nitrites must have come from the bacteria in my new system.

No great surprise really, but still interesting.

It's actually not that important for me to cycle my system, because I will be adding 100 litres of mature media from my test system. That 100 litres of media is currently coping with my eleven silver perch, so in the new system, it should continue to cope. As long as I transfer it in such a way as to keep it wet at all times, my nitrifying bacteria colony should find its new home welcoming. I'm told I should bury my old mature media from the small test system at about half way down into the new gravel media for best results.

Aquaponics - Gravel

Gravel.
Heavy.
Late.

I got some 20mm blue metal road gravel, as growing media for my new, larger aquaponics grow bed.

It looks like this.

And unfortunately it needs washing.

Also unfortunately, there is three tons of the stuff.








Actually it's not necessary to be too fussy when washing gravel as the system takes care of a lot of it, but this seems like very dirty gravel so it needs a good rinse at the very least. It's one of those things that takes so much work to redo if you don't do it right the first time, that its worth putting in the effort the first time.

I was hoping the truck might be able to deliver the gravel directly into the grow bed, where I could then rinse it with a high pressure hose. Unfortunately the grow bed was a bit too high for that, so it had to be unloaded in a pile next to it.

Its actually a good thing it wasn't able to be be dumped directly into the grow bed, because it had much more dust on it than I had anticipated.









Washing gravel is hard work with all but one method. Some bright person came up with the idea of just washing it with a fire hose when its in your trailer, or truck. By all accounts this seems to work well, so if you have that option, it's probably worth trying.

Its been a few years since I shovelled 10 ton of stuff from one spot to another, and in those few years, stuff has got a whole lot heavier.  Even when it only weighs 3 ton.

Unfortunately it didn't quite all get done.












Thirsty.

Aquaponics - Home made media

I did an experiment last night where I mixed some clay soil from my backyard with some crushed up goat dung. The plan was to try to make something like scoria, for use as a home made media for a grow bed, but just to see if it could be done.

And voilà!

First, I spread some whole dung out on a tray. Then I made a mixture of clay,water, and powdered goat dung. My theory was that the powdered goat dung would create thousands of tiny holes in the finished product. This would create some happy housing for the nitrifying bacteria required by aquaponics.

I then poured the mixture over the tray of whole dung. The design behind using the whole dung was an attempt to make it break into irregular shapes later on in the process.

Next I set it out to dry. If I was making an amount greater than this tiny test, I would have poured it onto the ground in the sun. But it was raining so I put it on some foil, and dried it on the fire. DONT DO THIS AT HOME! It can smell a little agricultural. When the yelling stops, you know your tile is dry.

Lay it out and build a fire over it. You want your fire to be 900 deg C or more. Clay will undergo a permanent chemical change at around 600 deg C (don't quote me on that number) where it becomes no longer possible to wet it back down to clay. The physical water steams off at 100 deg C, but at those higher temperatures its not just drying the clay, it's actually changing it into something else.

I actually fired mine in my living room wood burning heater, but to make it properly you need the kind of temperature that makes iron glow bright cherry red (~900C) It's quite doable in a decent fire.(a match burns at around that temperature).

A normal pot would crack if treated like this but because there is so much organic matter leaving the clay body porous, we can get away with it. It doesn't matter if it cracks anyway.

Next. Smash it.(see)

Its done (see top pic)

Delicious.

I have no idea if this is practical or useful in any way to anyone, but it was in my head so it had to come out.