For a rack system, yes, they'll work. Corns do like space, however, so taking them out quite a bit would be good too. I have some adults in 41 qts and one in a big 40 gallon breeder. They all fit and have space but being colubrids, they still want to explore and look for ways out. When I take them out on a regular basis, they seem more content but if I leave them alone for a week or so without much 'leg stretching' time, they tend to move around a lot more and test their enclosure.