I'm still trying to decide if I want to part with my huge bta. He is very cool! But I have him in a 55 gal. reef and when he is fully extended he is about 14 inches wide. He takes up a lot of room! My small percula finally decided to host with it yesterday, after 3 weeks. I have a small bta, about 4 inches, he's a very light green with almost pink tips. I would trade him for something small, if anyone is interested.