| Re: Nitrite and Nitrate Level Questions Well Nitrites, once a tank is fully cycled should never be detectable. You always want them at ZERO. Any detection could be harmful for livestock.
Nitrates on the other hand, can have detectable traces in your aquarium. For a fish only setup you want them no higher than 40ppm. For a reef setup you want them lower, at no higher than 20ppm. Fish can tolerate higher levels of Nitrates than invertebrates can. With a reef setup some even suggest lower Nitrates at no higher than 10 ppm. You want the lowest number possible here for Nitrates. |