My anemone just sucked up its base and went all weird and I wasn't sure what was going on... then I saw it expelling brown strands (waste I think). Anyway... the large clownfish in it ate the strands, swam away and then spit them out! She kept doing this over and over and pulling it out of the anemone to help it expel
It was very neat to watch! I guess that's one way clownfish help anemones 