No, not quite. The cement tubs are slightly larger, and we've found them easier. They are 19 x 25 x about 6.5. Also neglected to mention we don't leave mommas in those breeding groups to deliver, they have their own maternity rack, part of why the higher ratio works. If you're going with the larger cat litter pans I would say you could keep up to a 1:5 though, if you're intending (which it sounds like you are) to seperate them to birth.