There is none in the main tank since I took out the rock that had it on it. The frag tank had nothing in it but araganite sand. After I took out the rock, it started growing in the frag tank. Wasn't using frag socks and started using light on frag tank to do a reverse photo period. Everything in tank was dry when put in, only thing I can think it came from was the araganite sand I reused from someone elses tank, that I had washed 3 different times, final rinse being with RODI water. I have a 3600 GPH Reeflo Dart running the returns, a k3 on the 180 along with a 2000 GPH modded maxijet, the frag tank has a 3/4" sea swirl and 2 returns on it. Not sure flow is the issue. Nothing in tank now but sand, 17lbs of rock and a couple corals. Nothing in frag tank now, but a small rock holding down the frag rack and sand along with a few cap frags. Is the sand the issue then?? Trying to figure it out/cure/etc, before getting everything set up. I have read endlessly about dinos and still unsure what to do. In the frag tank, I stirred all the sand up really good, but it seems the dinos are as heavy as the sand? Added a lot more flow, and have it pointed to directly take anything to the overflow, which I now have filter sock on since they arrived from BRS.