I'm starting to think that all this bubbling or not bubbling is just within their normal range of movements and perhaps there is no environmental reason behind it. Whoever started this age old question of why they bubble, and then spread it throughout the hobby so we could all sit here scratching our heads needs to be found and punished! :pThis is a very interesting topic , I no longer have one in my tank but I wonder, is Flow is the Issue?
Too much flow and the tentacles lose their bubble???