It appears to have been Mr. Prickles, in the night time, with his teeth. He is now in excile.
For what its worth, he came in as a hitchhiker, thumbnail sized. he quickly obtained the trust of the corals and the innkeeper. all was well for 6 months or more as he diligently scrubbed the algae from the live rock and grew and grew and grew into a handsome velvety black baseball sized acro assasin. he struck in the night and blamed it on the astreas who were plucked from their homes and incarcerated in the sump. He could have gotten away with it, but he got greedy. last night he struck again, but during the get away he made the fatal (not really fatal) error of taking a nap just an inch away from the scene of the crime. Mr. Prickles may be rehabilitated some day but he will have to do the time...