Do low phosphates = high nitrates?

[Monkeyfish]

I have a 180g FOWLR with about 150lbs of live rock, shallow sand bed, 75 gallon sump, Reef Octopus NW200 skimmer, refugium with calurpa and cheato and a dual media reactor from BRS for GFO and carbon. The tank inhabitants are a 9 inch Emperor angel, 7 inch Picasso, 8 inch foxface, 3 inch 3 stripe damsel and an 8 inch clown tang. I feed heavy (Spectrum pellets, clam, squid, lance fish, krill, nori sheets and mysis shrimp) and figured the GFO would help control algae.

My nitrates were very high (100ppm). I've lowered them to about 40 via water changes and dosing vodka. I recently read that phosphate was necessary for nitrates to be "processed"/broken down - (not sure of the correct term). Is it possible that the GFO is contributing to the high nitrates by removing too much phosphate?

[sedor]

I don't think so. One can be higher than the other, but usually when I see high nitrates it means higher phosphates as well. I don't think they directly effect each other much at all.

[jasony816]

good questions, im in the same boat as you, low to zero P04 and have 5-10ppm N03 and would like to know also

[Randy Holmes-Farley]

It is possible that if macroalgae was your primary nutrient export method (using both N and P) and you drove down P with GFO, that the macroalgae may not grow as much, allowing N to rise.

[Monkeyfish]

Thanks.

[Randy Holmes-Farley]

:thumbsup:


Happy Reefing. :)