Purchased BP at 10 inches, 12 years ago. Now 4.5 feet long. Cage is an old TV console. Interior is 15"W X 33"L X 20"H. Water dish is sunken in floor and it will sometimes soak and even eat in the water. Floor is felt (glued down). Herp mat style heater in false floor under snapping turtle shell (hide). Driftwood branch in cage. Yes, it does climb on the branch and will occasionally strike a rat from above (so cool). It eats a medium size rat every 3-4 weeks after shedding (aggressive feeder). Temp ranges 80 - 85 F. Humidity at 50%. Light is an under counter fluorescent at 15 watts.

What is the reason for using a substrate? Seems like an added bother and expense. Clean up on the felt is easy, once a month pick up the poo. Cage size? When the snake was smaller it was kept in a 10 gal aquarium. Putting a mouse in there the snake would coil up in the corner (defensively?) and wait to strike. With the larger enclosure it likes to hunt. I'm presently thinking of building a larger cage so it can hunt more.
Not into "tubs", seems to unnatural.

Having trouble posting a picture. Cage is in my gallery.

All comments and criticism is welcome...