not 100% sure if this is what happened to a crazy sixline wrasse that we had in our 29...but it was fine for about 3 months and all of a sudden started acting VERY strange (doing loop-d-loos all around the tank...NONSTOP!!!). Right about the time that I noticed the weird behavior, I found an aiptasia on a new piece of rock that had been added to the tank...coincidence???? (maybe...but I enjoyed killing the aip!!!)