What size of adult male are we talking about? People tend to call the male an adult as soon as they breed which for some that is around 500 or less grams. My stud male who is over 2000 grams needs a little more space than most males. He is actually in my CB-70 rack. With his growth rate over the last summer I think he may actually make 2500 grams this coming summer as long as we continue to conservatively breed him this winter and not over breed to the point he starts loosing weight.