For substrate you have some options, you can try other coconut substrate like coco husk, or Reptichip. Cypress mulch also works well.

I use the Exo Terra caves that were mentioned earlier, but reptile basics makes some good hides too.

As for housing, Exo Tetras are pretty much like every other glass tank. Harder to heat and keep humidity than a tub, but with some modifications and a little work you can successfully keep snakes in them. I would look into PVC tanks though, easier to heat and they keep humidity better. Animal Plastics cages are popular but there's also Boaphile and Vision.