What type of substrate do you use?

SANI-CHIPS its 100% pure laboratory grade aspen in small chip form about the size of a pea but flat, no dust, very absorbant and still has a look to it.
Once I get my racks ill use newspaper... bacause its a rack. The SANI-CHIPS are cheap, I bought 2.2 cubic feet (about 15 pound bag) for 15 bucks at a reptile show.

I've got a cocoanut/mulch mix as my bedding for now. It seems to hold my humidity pretty well with both the UTH and CHE

I originally voted aspen but gave newsprint a chance and I'm loving it.

I use bark- Repti bark to be exact, and Imlove it :)

Right now I use Aspen, But I am switching to Coconut Bark as soon as my shipment comes in :)

I use repti-carpet as the first layer, then newspaper and a top layer of paper towel

is carefresh ok to house snakes in as substait?

Well, I don't have BP, but I use reptile sand as my substrate, and my snakes love it! Spot-cleaning the tank is actually pretty easy (I use the mini-sifter instead of the big one!) Of course, kings poo smaller than BPs... ^_^

Hmm, I would just like to update, seeing as how I have my snakes in different enclosures. I have them in tub set ups, and they are all on newspaper. Best switch I ever made!

My babies are on papertowels, subadults on Sanichips, and breeders on papertowels to prevent any chips from getting into areas that they shouldn't.

And all in tubs.