Oscar in hiding

Question
I Purchased a 2 in. very active Common Oscar a 4 days and placed him in a 10 gal. tank with 5 Zebra Convicts and a Blue Garaumi until I get my 55 Gal. tank from my brother. I noticed the Oscar midday in the cave all day. When I put a cube of frozen brine shrimp in the water he didn't come out. I forced him out by tipping the cave and he came out discolored with bright yellow eyes.
After a minute I noticed his eye and body color came back beautifuly, but he didn't eat. Also one of the 1 3/4 inch convicts nipped the oscar on the gill and the oscar didn;t do anything, now he has a small peace of skin hanging.
What could be wrong?

Answer
Hi Meno;

He's being terrorized in a tank that is way too small for so many aggressive fish. A ten gallon is even too small for that many if they are nice fish! You need the new bigger tank for them immediately. Those convicts are the meanest fish around and will kill your oscar. Or, he will starve to death because he can't come out without being attacked.

You could get a divider for the tank to protect the oscar but you will need to make a 25% water change every day. Thses guys are all messy and with it being overcrowded they will need that many changes to survive it all.

You have a lot of work ahead of you! I hope all goes well.....

At Your Service;
Chris Robbins