No experience dividing large tubs but animalplastics.com has racks that are very versitile. Pretty inexpesive also. I have one for my geckos it takes 15 and 32 quart tubs. 2 small tuna or 1 large tub per shelf. I use 32 quart for breeding trios and 15 quart to seperate them when breeding season is over. That route will also give you room for hatchlings down the road after you raise up your trio and breed.