Backyard Aquaponics
A place to discuss aquaponics

This isn't strictly an aquaponics question, but I figured you guys would be the ones who could help me with this, so here goes.

I'm experimenting trying to produce a sort of 'compost tea' for using on organically grown container plants so that the tea will have ready-to-use nitrates in, which the plants can use even if they potting compost they are growing in doesn't have all the necessary bacteria in to do the conversion to nitrate. So far I have a barrel of water with added compost from my compost heap, urine (to supply the nitrogen), some leafy weeds I pulled up from the yard and a handful of rabbit food in case the bugs needed some energy. I'm bubbling air through the water to keep it oxygenated, as I think the bacteria I need are aerobic. But am I missing something? Do the bacteria I need live in the water, or do I need to pass the water through a gravel bed? And how do the bacteria get there in the first place? Do I have to introduce them from somewhere else? And assuming they are there, how long is it likely to take for nitrites and nitrates to start appearing? I've had the stuff bubbling away for a few days now and nothing seems to there yet. Or am I completely barking up the wrong tree?

Any info, advice, whatever, gratefully received!

I would suggest reading the Basic Info and useful info sections of the forum to learn about the nitrogen cycle. And probably the fishless cycling thread in particular could be of assistance to you.

I expect some bacteria is going to manage to live on any surface you have available, but, pumping the liquid through a barrel of gravel will provide more surface area for the conversion to happen quicker. And pumping through a barrel or bin of gravel will probably aerate better than just running a tiny aquarium air stone in the barrel of compost water.

Yes I think an aquaponics type set up probably can make you nitrate rich water for your plants better than simply aerating compost in water. Aerated compost tea is really meant to provide a boost of bacteria in the tea to the plants and soil, not necessarily provide converted nitrate. You might even try and look up my old Pee Ponics thread. Something like a barrel ponics system where you put a bag of compost and add your ammonia source and let it cycle would definitely create some rich water for use on container plants. The gravel grow beds would even make a great place for rooting cuttings and stuff.

I'd read the intro to the nitrogen cycle - the bit that I wasn't certain of was about the need for surface area, which you answered nicely for me, thankyou!

I'm off to read up on the fishless cycling, have a think about how I can inocorporate a gravel bed to my system, and then investigate Pee Ponics - a name like that is the way to a Burra's heart!