I am not a fan of keeping them in tubs either. And I seen some videos saying that you can keep a BTS in a 41 quart(FB-70,V-70,CB-70) tub, which I think is nothing but total crap. Imo rack systems are best for ground snakes which prefer belly heat, but are no good for basking lizards. I realize that many breeders often want to keep the maximum number of animals in the minimum amount of space. But imo anytime you are breeding animals, you should do more than just meet the animal's basic needs.I'm not a fan in keeping them in tubs for pet keepers, like BHB has a vid about it. So any vids imo saying that BTS would thrive in tubs, is nonsense to me because of their personality.
Why wouldn't make more sense to get a 4' long x 2' wide x 6' tall storage(5 shelf) rack from Lowes' or Home Depot. And custom build 5 PVC or Melamine cages, which are about 46-47" long x 23" wide x 12-14" tall - to keep 5 BTS in, instead of using a rack system. As it would certainly give them be more floor space(7.3 sq. ft. vs 4.0 sq. ft.), double the height, and likely more enrichment in their cages.