Ink... not too sure what your experience is with the larger tubs but your statement that its "more open air to heat" is incorrect... The difference between your tubs and mine is 6inchs... if you do some tests youll see the extra 6inches doesnt make it any more challenging to heat... I keep all my snakes in tubs this large and I will agree they may not "need" the extra space but given the extra room all of my snakes "climb" if thats what you call it...