Backyard Aquaponics
A place to discuss aquaponics

And here is yet another article about zero discharge Aquaculture systems that may be helpful.

http://growfishanywhere.com/media/5575/ ... c_2003.pdf

ummm great design but I'll only add aeration in the MBBF alone. aerobic digestion is less effective at breaking down solids compared to anaerobic digestion. scale your MBBF to handle the extra load and everything should be ok.. yea I tried molasses a while a back. surprisingly its an acidic compond. but my only problem with it is that it darken your FT water if u overuse. ie if its your source of supplements to the system.but all in all a great addition to help denitrification.

Cookie, I guess going between aerobic and anaerobic in the MT could be the way to go. The thing is when you first use air pumps in MT for aerobic mineralization you break up the solids. If you then turn off the aeration and let it go anaerobic wouldn't that make it easier for the anaerobic bacteria to break down the solids further?

Something that has me confused is that when you are using anaerobic denitrifcation it says that it will effectively remove phosphates. I cant see that being a positive, unless you have too much phosphate in your system. My current measurement of phosphate in my system was 1-2ppm so I wouldn't want to remove any more phosphate. My nitrates are still high160+ppm..

Too much phosphorus means algae.

no its the other way around from what I read.. aerobic bacteria takes up large amount of phosphates to develop themselves and reproduce. However bacteria releases phosphorous into the water within 1hr exposed to an anerobic zone. anaerobic digestion releases ammonia simply because its converts protein into ammonia. the destruction of protein release phosphorous by the destruction of the phosphorous nitrogen linkages in protein compounds.. this process I believe is more effective if you can maintain ph a lil below 7. rule of thumb any process that can physically reduce the mass of any waste product implies digestion is occurring.. reference it to food entering the human body.. it should give you a better idea.

Check out this article page 25. Dissolved Phosphorus in Regular RAS vs Denitrifying RAS..http://archimer.ifremer.fr/doc/00021/13190/10273.pdf

you should try a next source to double check.. but from everything I read phosphorous is released in anaerobic digestion... but instead of reading about it.. you seem so have the means to test phosphorous. so what I'll suggest is remove some waste from your filter and add even amounts into two separate identical container with same volume and depth. the aerated one and leave the other anaerobic. measure pH. conductivity. phosphate and any other reading you wana monitor before to get a benchmark. then maybe after 3 days do a test again and see for yourself which release more. btw you will have to peroidically stir the anaerobic one at least once per day to distribute the nutrients evenly.. I'll love to hear your finding. and it will surely clear up the misinformations. what you think Swed..?

oh btw for quicker digestion.. limit the amount of water you add into the containers of waste.

Cookie,
your suggestion is a good one. But I don't think I will have the time to do that test right now. And from this article I have found that phosphate removal becomes more efficient with time. I will continue monitor my phosphate levels in my system and keep updating to this thread.

http://www.jscimedcentral.com/ChemicalE ... 1-1006.pdf

Cookie, after reading page 5 of the article above I am getting a bit confused about the removal or release of phosphorus. I believe from reading the article that you are right if the conditions are just right.
If conditions are wrong you will actually remove some phosphorus. (I will be testing my phosphorus levels)

See excerpt from article page 5 below.

Then, wastewater
flows by gravity to the subsequent anaerobic stage where DO
concentration is below 0.1 mg/L and NO3
- concentration is
less than 0.5 mg/L. In the Anaerobic stage, PAOs uptake VFAs
and accumulate them in their cells in the form of PHAs. As
PAOs take up VFAs and store PHAs inside their cells, they also
release phosphorus into the water. Therefore, the phosphorus
concentration in water highly increases in this stage. Then,
PAOs enriched with PHAs enter the Aerobic stage where they
oxidize the cellular PHAs as a source of energy and uptake both
the phosphorus already present in the influent to the bioreactor
as well as the amount released by the PAOs in the Anaerobic
stage.

yes that document reference seems to match what I read as well.. the bacteria uptake Phosphorous in aerobic conditions and releases it as its exposed to anaerobic environment as quickly as within 1hr peroid.

I always suspected that when Ryan talked about different reactors to balance nutrient levels, that he had both aerobic and anaerobic reactors. Perhaps multiples of both with different supplements reacting in them.

I would love to pick that guys brain :-). I think you are right about him using multiple different aerobic and anaerobic tanks.. In the meantime I will keep on experimenting. Ronmaggi, did you ever try one if those RSG filters for denitrification?

No, I use plants for that.