i got a fullproof plan for ya. do hyposalinity on the liverock. it won't kill the bacteria, but may kill a few copepods. best part is aiptasia is a kind of anemone which are really sensitive to salinity changes and if you do a drastic salinity change from 1.020 to 1.010 in a second, they will implode. worked like a charm for me, but just to be on the safe side i kept it in the lower salinity for a little while longer(over night). oh and i did it in a seperate container with an airstone.