I am gonna disagree with the other member here and say you can have your 6month old in an adult cage. I have had my panther since 4 months old in a 30X 18X36(this is what the Kammer's, of Kammerflage Kreations keep all their adults in. I let him hunt his food and he never had a problem. I think a 6 month old will do fine in a 24 X 24 X48. This is just MY opinion. I don't think there is a need to buy a smaller cage and upgrade to a larger unless you are dealing with babies.