I had heard that some corals can help lower and intake Nitrates and that Xenias and Zoanthids did this. The reason I am asking is because my Nitrates are right around 40ppm and I have done water changes 20% and I have a 125 gallon tank. It finished cycling the second week in June and all I have in it is Live Rock and two damsels. I added some blue leg hermits due to diatoms but then I left my lights off for two days and they were gone. I do not over feed my fish because I only have two and I use RODI water. The ammonia, PH and Nitrites are all good. I was just curious if anyone has used corals and if they really do work in lowering Nitrates. I know some soft corals actually do better in high nutrient water.