I have a 10 gallon aquarium with a goldfish, black moor (named Dumbo) and a pleco in it. A couple of weeks ago i noticed the black moor was missing a scale or two but I didn't really see much else wrong with him and he seemed fine. The tank is in my sons room so I forget to go turn on the light sometimes until the end of the day. When I went in there yesterday afternoon to feed them I turned on the light and was horrified by what I saw. My black moor was so beat up it was so sad. His fins were all shredded and he was missing many scales and just floating around in the tank, every once in awhile swimming. I took him out and put him in a fishbowl so hopefully he can recover. I don't think it was the goldfish that did this and the only other one in there is the pleco. Do they ever get aggressive like that? Could it have been that the pleco didn't realize it was a fish he was doing it to, being that it was dark in the tank? Does anyone have any info on what I could do to hopefully help Dumbo survive. He is pretty much just laying at the bottom of the fish bowl now. Thank you for any suggestions and insight into what might have happened.