Just flushing the water out of its system. Mine tends to do "water changes" a day or two after I change the water in the tank.
it's a filter type.
Mmm I'm curious on that one as well. I've had anemones in trickle filters and main tank with sump and they still always deflate. It's their way of expelling "used" water which is what they're full of.I know, just curious how it relates.....