I have always used critter tank or breeder tanks. But I need more room .So I'm thinking about tring the rack system Do you put the flexwatt on the back of the rack or on the shelf. what about basking light? I use a small cat litter box for a water dish in my 40 gallon breeder tanks so they can soak if they want. I have one female that is over 1800 grams she fills the litter box (water bowl) full of snake. When you use tubs can you still use big water dishes? Any reply will be helpful. Thanks