Hello and welcome to 3reef first of all!
Now, regarding nitrates...nitrates if you had to have one of the three in terms of cycling and water parameter toxicity, nitrates are the least detrimental as compared to ammonia and nitrites!
That being said however, excess nitrates increase the growth of plant life(whether it be macroalgae or microalgae). This could cause corals problems due to them competing for light with the plant life. Nitrates are a source of fertilizer-
Nitrate excess will also cause stress to fish causing behaviorial changes and possibly problems regarding reproduction, though we really don't have to worry about this as much...
It is good to have some nitrates in your water as it is a source of food for corals, and Tridacna Clams more so. <10ppm is ideal with more than that for a period of time will lead to the above mentioned taking place. _________ 125gal.w/Mag9.5 return(dual megaflow)>Mag7 pump Aqua Cev180skimmer.Wave2k Hamilton Reefstar(2)250watthqi(mh)pend.a Yellow, Naso Tang Red Lip Blenny Percula Clown Demoiselles Niger Trigger F. Wrasses Ceriantharia Orn.Shrimp and Stars Hermits Queen Conch asst. snails> Stars Zoos shrooms Montipora Brains Gorgonians Favia Turbinaria(large+small polyp) Acropora Xenia Tridacna (CroceaMaximaSquamosa) Leathers <35+75gal.reef tank as well> 
"IF THE PHONE DOESN'T RING...IT'S ME"  jb  | 
hi everyone 
