I turned off the my aquarium lights yesterday before I went to bed like I always do and today I woke up to my Black Tiger Oscar with a big piece of his skin missing on his head....And he's just sitting at the bottom of the tank breathing heavily and not eating. He seems sad and in pain. My Oscars have got hurt before from my holy rock but never this bad. I hope he's going to be o.k....I might end up taking out the holy rock but my Texas and Blood Parrot love it.