Carbon dosing and sulfur denitrator in the same system

AndrewJ · Apr 27, 2017

I believe this is a chemistry question: How do carbon dosing and a sulfur denitrator interfere with each other in the same sysyem?
In Red Sea's Reef Care Program Algae Control, pg. 8:
"Do not use NO3

O4-X in conjunction with sulphur based de-nitrators or phosphate and nitrate removers as the different methods for nitrate and phosphate reduction will cause interference."
I believe I understand, taking into account that bacteria consume phosphate and nitrate in a ratio, why using something like GFO would cause diminished results in nitrate reduction when carbon dosing.
I do not understand how using both systems in the same aquarium would interfere with each other.

Dr. Reef · Apr 28, 2017

not a chemist (just a doctor) but i used vodka dosing with sulfur denitrator for over 1 yr and had no issues, kept nitrates at 0 and phos under 0.05. not sure about nopox. maybe other will chime in.

Randy Holmes-Farley · Apr 28, 2017

Both processes use nitrate primarily, and a small amount of phosphate. I think as long as you are careful to not drive nitrate too low, you won't have an issue.

That said, I'd probably phase out the denitrator if you are going for carbon dosing (which I prefer as a method since it feeds many organisms and doesn't deplete alkalinity the way a sulfur denitrator does.

AndrewJ · Apr 28, 2017

Randy Holmes-Farley said:
Both processes use nitrate primarily, and a small amount of phosphate. I think as long as you are careful to not drive nitrate too low, you won't have an issue.

That said, I'd probably phase out the denitrator if you are going for carbon dosing (which I prefer as a method since it feeds many organisms and doesn't deplete alkalinity the way a sulfur denitrator does.

Thank you!
The sulfur denitrator I have is convertible to a calcium reactor. Are there any issues I should be aware of if I use it as a calcium reactor?
That asked, I probably won't convert it. I'm thinking I will put it on my FOWLR tank instead as a denitrator. I would then carbon dose and dose two part on the reef tank.
Thanks again!