Hey Aaron,

I do use flex watt on the back of each rack (that's actually two neo racks stacked). Each rack has a 8" by 20" (guessing measurements but you get the idea) sheet of flex watt on the back of the racks controlled by a Helix 10000.

Seems to work great. There are small ceramic water bowls you can buy that fit in there nicely as well.

Dave
DNS Reptiles - Milk Snakes