Kristy I really am surprised its there. I had issues with phosphates but have run a phosban reactor for about a month now as well as running some other additives to combat it. I have never show any nitrate issues, but while I was on vacation I had my heater die and lost a rather large clam. Not sure but I still showed pretty much nil for nitrates etc even after testing that. My tank temp dipped for what I can guess was no more than 15 hours as it was still hotter than room temperature.

Other than that I dont have much livestock in the tank at all and definitely am not over feeding anything. This is really a surprise to me as I also hadnt introduced anything in at least a month and a half and this colony though from an LFS seemed to be clean. I also dipped everything that has come into the tank and used dried rock that sat on my porch for 4 weeks in the sun. Even most my frags get reset onto my dried rock before they enter my tank.