i would question what kinda breeder that is, it is riduculous to cramp leachie in exo terra nano, it is ok while they're babies and smaller leachies. Same goes for cresties, medium sized plastic keepers are ok while they're babies, that is how I keep mine, 8-12 m olds are all beeing transferred into 12x12x18. for adult minimum size is 18x18x24. My breeder tanks are all 30x25x35 and I can't say they're too big. Of course the tank i want for leachie is a bit overkill, but have you seen granterra leachie? the 1 pound or so monster? crested, gargs, leachies are all tree geckos, thus too big of a space will never be an issue for them, the bigger the better, especially for leachie who likes to sit high up in the trees

same actualy goes for tree frogs, say waxies, 3 of them will be perfectly fine in 24x18x24, but some breeders in Argentina keep and breed them in 7 feet tall enclosures and I'm pretty sure waxies are not complaining
