They say that any
NO3 at 40 + can have a negative effect on corals and fish.
Adding
LR is a good way to keep
NO3 in check as well as a refugium. Before I added a fuge on my 125 reef my
NO3 would run between 5-20 before water changes would bring it back down. With my fuge (knock on wood) my
No3 is at 0 and I go several months between changes.
Regular
WC will help keep
NO3 in check and lower it over time.
5-10 is good
IMO and nothing to be alarmed at.
__________________