Algae eater fish is missing?

did you check the interior of the filter? I had one swimming in there once. I also had a plecostomus fish jump out and suck it self to the carpet. Sorry I hope you find him/her? In all my years of fish I never evr had a black moor harm anyone else in the tank. Do you have a cat? My cat used to fish from where the little holes are where you filter leads into the tank.