Well, you should try to find the platy, and notice if the
ammonia goes up, then you know it's still there. But you say your platy was a dwarf variation, and angels will not hesitate to ambush small prey (when you're not looking). As a general rule, put only fish that grow up to 2"+ with angels (any species that does not nip, like most tetras). Dwarf platys get to about 1.5", so he was a gonner to start with. But your angel should still ahve his normal shy personality. Maybe you should
QT him for a while (rehab-session), introduce some standard sized platies instead, and then re-introduce William. Should anyone object to this information, you're best off listening to them, my suggestion is just my own 2 cents
