I know he ate them, I watched that, but that is normal for any shrimp to start devouring a dead fish. I have seen him chase my newer fish around but I haven't seen him kill any of them. It isn't a common thing for cleaner shrimp to kill fish, I am just paranoid because the cleaner shrimp I had in my last tank did start killing and eating my fish. I wasn't sure why they were dying until one day I watched him hunt and catch my dwarf lion. Once I got rid of him I had no problems. I think my problem now is a mantis shrimp or something in my liverock. It is a small tank so they wouldn't have any problems grabbing a fish.