DOC (NoPoX is a type of DOC) will handle nitrite in normally two pathways - uptake (together with phosphate) by a growing population of heterotrophic bacteria. If phosphate hit zero - this route is closed. The other major pathway is denitrification by (often) the same bacteria in anaerobic environment (bi-pure and deep in sand) there they use nitrate instead for oxygen in their metabolism. They need some phosphate to for their growth but when denitrification is established - it use very much more nitrate than phosphate. This take time (to establish a denitrifikation) so I would wait a month or two before any changes.
Sincerely Lasse
Still getting my bearings on the Redfield ratio but if I understand it correctly and based on what you've provided then regardless of nitrate levels the phosphates becomes the limiting factor and best practice would then be to elevate phosphates to 10:1 of current nitrates while dosing NoPox or carbon dosing in general. Is my understanding correct or flawed?
I'm in the process of testing several theories based on my experience since the 70s supplemented by what I've read over the decades yet wasn't able to implement for various reasons. In my current 20H I created a large enough area to allow depletion of DO where denitrification can occur although currently still fishless and wanted to test the assumption using NoPox as my carbon source. Goal is to rely on detritus post addition of fish and corals.
Due to my approach to fishless cycling which incorporates incremental amounts of ammonia to raise the ability of the nitrification biomass the nitrates get to above 200 ppm and post 50% water change is still hovering around 80 ppm. Didn't want to go 100% because I want nutrients in the system to test my theory. Have added NoPox and didn't see a reduction therefore I ordered
NeoPhos to supplement my phosphates to bring them to the 1/10 ratio. Since lights are still off there is no current ugly phase and don't expect it based on past experiences.
Therefore, before I go mad scientist and add phosphates to bring my estimated ration to 10:1, am I getting this right as to my high nitrates assumption not being the issue and merely the addition of the correct amount of phosphates will allow NoPox to bring the levels down. Assuming this is correct. Logically sounds about right then future maintenance will be as easy as increasing phosphate levels to manage nitrates as a supplement to the denitrification that I expect will be occurring.
BTW, when i first added NoPox the dosage was three times recommended based on the fact my nitrates were through the roof plus not having fish allows me to purposely push the limits to test my theory. Water never became cloudy although it did get extremely yellow which GAC solved. Seems to indicate the hetetrophich bacteria may have had suffieicent substrate or the excess dosage was not a problem because of the high nitrates. Could be the nitrates receeded but were so high that even reduced was above the testing range.
