Just so you know, a snake (especially one the size of a BP) has way too much "output" for a bioactive enclosure to naturally get rid of. What you'll likely end up with is an unhealthy mess & potentially a sick ball python. If I were you, I'd abandon this idea. It's not easy to get it right, even with smaller creatures. I know there are enticing ads around trying to sell you on this idea, but it's not feasible for what you're keeping. And it's not going to get around providing the proper substrate for your pet, as you recently asked about (how to save money on?).
Thank you, for your input. I'll do a little more research into why I *shouldn't* instead of why I *should* this time.