I think its a fish that the person needs alot of experince before buying and tank should not be less then 6-10months
Just see to many people buy them and want to know why its dead after a week
I have a female bellus and she is definitely my favorite fish. I think a 75 would be fine for a bellus, but make sure you have a mature tank (at least 6 months) as these angels love to eat pods. Mine swims all day long picking at my rock.