I purchased a juvenile Blue Hippo Tang and introduced him to my tank 4 days ago. I already had 2 clown fish, 1 yellow tang, 1 mandarin goby and 2 cleaner shrimp...the hippo tang was the last fish to go iin. All of my other fish have been doing well the last 3 weeks. This Hippo Tang stays in my live rock most of the day...almost wedging himself at times it seems lol...He's about 2 inches in length. When he does come out he swims and looks great but then spends most of the time in the rocks....Is this normal? Again he's been in the tank about 4 days. He comes out and eats with the other fish too.