Never thought about it for aiptasia. Luckily I didn't have an issue with them in my current tank. Makes sense though. Yeah, it is definitely an at your own risk method.I remember reading this at the time. Thanks for reminding me. I think I may try a few spots for fun to see if it helps contain it. I have used boiling RO/DI to kill Aiptasia in the past as well. Works great if you are careful or can remove the rock to a bucket.