I have one that got stuck in the power head fan. TWICE. First time I turned it off and it released its self. Second time wasn't to good. The tentacles were trapped round the fan. I gently removed it and it ripped the tentacles off. Thought I was going to loose it. But after a few weeks it had heeled. It's difficult because it's in the filter and you can't turn it off! Try feeding it a piece of prawn to see if it will wrap round it.