The shark is from cooler water however i did the research and they do very well in warmer tanks, I keep mine in the 78 f area. He is very active moving from one end to the other. 8ft gives him good swimming room, my rock is in the middle. It's a walk around set up. But YOU CAN'T FIGHT NATURE. after 6 months he has discovered smaller fish in the tank with him. A large green chromis was bit in two. He ate the back side but left the rest. It was a perfect oval bite as clean as any sharp knife would make. I have about a dozen green chromis in the tank. One less each night. down to six. At least he is not a pig about it. It's his nature so alas Green chromis you will be no more. I will find him a new home. It doesn't harass any of the fish during the day, appears to be a great community fish. Unless your a little guy. He is doing great over all health, loves shrimp, I use to feed him by hand but after seeing that chromis I use a feeder stick. I like my fingers. so would he.
"Sharkey this fish is the hardiest in my tank
no way is he going to die. They are a traditional game fish. Good eating I hear. You can catch one for free, but the retailer charges $100.00 something is wrong with that.