I've got a couple big females that would look huge in a 75 gal aquarium, but would thrive in it with gusto. Ball pythons like tight spots. These females are in 41 quart tubs(33' x !7') and doing fine. If your BP is a baby or juvinile, the 75 gallon is on the big side for it. On the other hand, if temps and humidity are monitored closely you should be fine.