Just started about 6 weeks ago with the aqaurium hobby. I have a 55 gallon tank with 80 pds of live rock. I have a maroone clown, 2 firefish, a yellow tang who is new, a mandarin, and a marine beta. My yellow tang is very aggressive toward my beta. He doesnt mess with any of my smaller fish, but will not leave alone my beta. He chases him around to all the hiding spots and nips at him from all angles. . I love my beta. My beta is about 33 inches long, the tang is medium size. I just removed the tang, having to completely disasemble all my rock to get him. Instead of giving him back to the store, i released him into the ocean. Not sure if that was dumb, but I did it. My question is why was he trying to kill my beta, and will he live in the ocean. I live in miami bch, florida incidenatlly on the beach so it was a fast walk downstairs.