Backyard Aquaponics
A place to discuss aquaponics

firstly joel got the book the other day and very good reading,

secondly I have started a aquaponics system with aeroponics as the growth medium. I have uploaded the photos of plants growing over a couple of weeks to the album. i am interested in whether anyone else has started a system other than those with the beds.

I am ialso in the process of setting up a second system, larger in water volume, that will hopefully have a continous flow beds as well as allow for more aeroponics and a trial of tomatoes, lettuce, beans and herbs in nft to see how the different systems run,

G'day Nick,

Fantastic photos, so how are you running it exactly? Your growth is looking really good.

I have tried a small experiment with NFT, well, not NFT exactly, but large diameter poly pipe with holes drilled in it and mesh nets like in your system, basically the same.....

So I guess the style your using in your systems is what some people would call DWC..? I think it means deep water culture, maybe...
But basically, are the roots of your plants sitting permanently in water? It's just a little difficult to figure out exactly whats happening from your pics alone..

Great to see some variety in system, please tell us more.. And thanks again for the pics, keep em comin...

Joel

the roots of the plants sit in the air and are sparayed by sprinklers the same as in normal gardening. This water then drains back into the tank for the fish. the system runs on for fifteen minutes and off for fifteen minutes, for the first five days or so the system runs continuously to help get the roots through.

Both systems run normal aquarium type biological filters. This limits the amount of solid waste that is pumped through the sprinklers. I have my water checked at work on the weekends. At first there were issues with ammonia, but a week with no change to feeding regimes and it cleared itself up.

I also had some issues with iron deficiency in my mint and basil. This was solved by then of some chelated iron to the system and it solved the problem in a week or so. Has any one seen this issue in there systems?? it presents in the plants with yellowing between the main veins and normal green veins.

ahh yes, excellent... I've read about aeroponic systems, some done with micro sprinklers, and others done with misters.. Great to see that you've got it working well..
I've also seen another very similar version of aeroponics, except instead of using small sprinklers or spray misters to get the water onto the roots, he used those small ultrasonic fog makers, Foggers. He has a side by side comparison with with the fogger and normal sprinkler aeroponics and claimed that the fogger was quite a bit more productive.. At that stage he was still testing things using pure hydroponics, but he was planning on converting it over to aquaponics.

Yep, I add Iron chelates to my systems every couple of months or so, works a treat....

I understand that iron deficiency is quite common in plants grown in aquaponics systems. It's because the pH is too high (and the iron at higher pH is not available for plants to use) for plants in the compromise between fish health, bacteria health and plant health.

I did have this problem in my mini-aquaponics system too. I found that the pH constantly wanted to rise in my system. I solved it by slowly adding acid to the water to bring the pH down to about 6.3. The fish died, but the plants looked great!

-Vlad

Vlad,good to see you here.

What sor of fish did you have?

i've had my silver perch down to this PH. What you may find is that the deaths were a result of dropping the PH FAR too quickly and/or the fact that the nitrifying bacteria pretty much go on "strike" at this PH and your ammonia levels will go through the roof. (Granted, its less toxic at that PH)

Interesting note about availability of minerals at different PH's.

I think i have a jpg of a bar graph that shows availability of different minerals over the PH scale, will try and find it and post it.

There is a great link in the "links" page on performance of nitrifying bacteria at differing temps and PH.

Steve

Yeah, I agree. I likely added the acid too quickly, and it did stall the ammonia reducing process... I used to have this charted and remember that there was a clear relationship there.

In hydroponics, depending on the crop, one often wants quite a low pH of 6ish. Unfortunately this seems to contradict the bacteria preferences, so I don't know how one could avoid chelated iron with some crops. I'll take a look at the nitrifying backteria link you suggested. thanks.

I was growing a fish from the store that they called red minnows... they claimed that these fish would be more hardy than goldfish, and they were quite inexpensive. I don't know much about fish, especially various fish species, so I don't know what they actually are. They did seem quite hardy, though, and a handful survived considerable abuse as the system stabilized.

-Vlad

I know that eathbound adds chelated iron ever so often.

I think most minerals are still fairly available at ph 7.0

Steve

Yep, I add chelated iron as soon as I see any signs of yellowing, and thats not that often...