here is a quote from ron shimek and keithclarks article on cirolanid isopods
"If you notice a cirolanid in your tank, and it leaves the fish, there is almost nothing that may be done to catch it. They are very fast, small, and quite capable of avoiding a net. And if it is a pregnant female (remember all isopods have brood pouches), and the brood hatches, you have REAL problems. There are only three courses of action in this situation; and I truly am not jesting about these responses. The first is to remove all the fish from the tank and wait the two or three months until you are certain that all the isopods have died from starvation. The second solution is to effectively nuke the tank. Remove all live rock and discard it as the isopods may hide in it, and as some of the isopods bury in the sand, you should also remove and discard the sand.
You may of course take the third option and do nothing. The most likely outcome in this situation will be that the isopods will kill your fish one by one. You may not even know they are attacking a fish until the fish is dead. Some years ago there were several large sharks that washed ashore in Florida. Examination showed that they were all killed by cirolanids that had burrowed into the shark and eaten their hearts.
Masterfully designed predators, these isopods. Hope fervently that you never have to deal with them." -end quote
scary stuff indeed. if you read the rest of the article you'll hear how when disposing of an isopod the isopod attacked his student and started eating her flesh just like it would a fishes. no joke.
