I use 28 qt. sterilite tubs in my rack. The biggest female i have is around 1500 grams, and she seems to be doing fine in it.

Alot of people say you need a 41 qt. or CB-70 sized tub for large females. Guess i'll build a new one when my females get up to that size.

So it's hard to build one size rack for all snakes. I think adult males do fine in 28 qt., but you'll eventually need a bigger tub for your real big females.

I use 4" flexwatt with my 28 qt rack with a herpstat.