Backyard Aquaponics
A place to discuss aquaponics

Just kicking an idea out there. But (big but) we know bacteria convert ammonia to nitrite, nitrite to nitrate. Nitrate taken up by plants.

It seems to be a fact that BA with gravel beds can go a step further and through further bacterial processes cause mineralization of further plant nutrients hence flowering plants in backyard AP systems but not in commercial systems that remove solids before they can be exposed to further bacterial action. Chalk one up for BA.

Now im really attracted to the idea of Redclaw because thier detrivors (eat decaying material) and will eat just about anything in the system so it seems to me far easier to get away from commercial feeds(which a hell of a lot of us are very interested in doing) with redclaw than any other species.

But this got me to thinking, we all know that extra feed in the system wether its eaten or not causes causes extra ammonia, nitrite and nitrate to be released into the system. Why? Because regardless of wether fish or crayfish are eating it bacteria and microflora are .Just as they do in nature.

The Question is could a "properly cycled" system with bacterial breakdown of detritus as its majour provider of ammonia work.??

Im not talking about gettting away from fish or crays completly but if we could have a system that wasnt entirely reliant on ammonia from our "usual sources it would give us system design and stocking at least partially independant of stocking rates.

It also seems that a large portion of the natural nutrient uptake of crays is the bacterial slimes that occur naturally which would argue for them being ideal for shuch systems.

Its just an intriguing idea ,were not talking about anything that doesent occur in natural systems anyway and seemsto be just another way of having a system that more closly mimics a natural system. Just as putting solids back into the grow beds more closely mimics nature,and actually has benefits even though it may not be for intensive "commercial systems.

Manifesto Ends.

Tim B ... the ultimate extension of your thoughts would probably be to utilise waste water from treatment plants through big grow beds.

But would we feel comfortable eating the produce??

It's not really anything different than what has been done throughout history... using "nightsoil" to feed the vege garden.... and is still practised in many countries around the world.

There are now also many waste water treatment system (sewerage or otherwise) that discharge to trickling weed/reed bed systems which filter and treat the discharge to a highly potable standard which can be then discharged to natural waterways.

The concepts aren't really that different.... just a matter of some being more "open" systems and others being more "closed" and efficient/attractive in terms of water conservation and/or food production

Perhaps we could incorporate fish/crayfish into our treatment systems (giant AP systems), but again would we be comfortable with consuming the end product.... most of us probably wouldn't.... many wont even drink the water from treatment stations although it's in reality probably cleaner and of a higher standard than many of the town supplies

Roz im not looking that far out. Im only talking detritus not sewage. its a fact that ammonia is produced when certain bacteria and fungi (water bourn) break down organic matter. more than a few hours in the tank and any veg matter has a "halo" of slime round it in my small system. Im betting that this is already going on in well established gravel systems and that how far it goes may only be a matter of the limited decaying material in the system.

There are some amazing projects out there utilising grey and black water for plants with the end result being clean water, a wetland type set-up will clean most anything organic up if it's planted properly.

Worth googling greywater and wetlands together for more info.

At the end of the day I`m in it for the fish/veges and the fun, If the breakdown of detritus is going to help me obtain them then I`m all for it.But (another HUGE but) the only time I can see it helping is if a lot of fish died and I needed ammonia in a hurry, and even then I probably would just add nutrients to the system until I restocked
Don`t get me wrong, The idea sounds good in theory, I just don`t think its practical for me

I hear ya gnash and its the same for me ,But if it meant i could have a lower stocking density but grow just as many veggies and not have to fork out for as much specialized feed that is bought at a huge hydrocarbon subsidy then id like that

I think you're correct. look up fishless cycling you'll find your answers there.

will do AA. Maybe i shouldnt have started the thread as 'do we need fish or crays?' but i knew it would ahve the mob baying for blood!

Tim - if you want to see, run a little test tank and bed and feed the tank with vegie scraps only. Stop the solids from getting in the pump and see what happens. Reckon it would probably work.

I too am in it largely for the fish. My problem is getting enough grow-bed space to stock at the rate I would like. Materials aren't cheap.

Had a look at fishless cycling AA, interesting. Of course its from the point of our bretherin the aquaria people who dont want ammonia in their systems, whereas ours are set up to handle higher loads. The question is can breakdown of organic materials (veg scraps for instance) supply at least part of a systems ammonium requirement if we have the right conditions, and if so are those conditions detrimental to the rest of the system for AP.

Vb as i said its just kicking the idea out there, if we dont question we dont learn! And yes i can feel a little trial system coming on. Again though it would give us flexability with stocking rates ,have fewer more pampered fish in a less stressfull environ and allow those that have space issues to have larger growbed to fish ratio. Im a little bit different in that my focus is more on fresh veg and less on fresh fish.

Tim, i like the way you think.

one point, i think that although decomposing foods will give you an ammonia output, i'm fairly sure they raise the O2 requirement......which if you have no (little) fish might not matter as much........

asl vb said, give it a go on a trial tank. questions are good. theories should stank up to questioning. go, play, have fun, and LET US KNOW

Was waiting to see if youd bite and yes im thinking good O2 is the key my only impediment is a good aged system that has that layer of muckand some worms, i suspect those with beds like this are already getting some ammonia from that beautiful compost heap in the bottom of their grow beds

I agree regarding the DO. Reckon that to aid the decomposition process and to stop it from stinking so muc, would want to keep things moving pretty well.

yep