In the research I've done I've seen a lot places state you need a drainage layer, however I've seen a lot of people also not include them. Should I include a drainage layer for when I make my boa's bio setup or no? Why or why not? I can't seem to find the reasoning for why some do and some don't online and thought I'd see what you guys think.

I could see some reasoning being burrowing down to the drainage layer, but wouldn't a screen or something prevent something like that? Especially if you provide enough substrate for them to still adequately burrow themselves. As well as tubing down into the drainage layer so you can drain it if it becomes to much. I feel like I would have more control over the humidity this way.

With enclosures without the drainage layer wouldn't there be more likely of scale rot or at least be a pain to try to take away humidity when it becomes too much? Or if it gets over watered that means it would need to be replaced and ruin the cycle of setup?

It doesn't seem like very many people are doing bioactive setups for boas, unless it's a BRB or maybe I am just not looking in the right place. Is this something I should do for a BCI or no? I honestly don't see the harm in it at all and I think it would do him good humidity wise.

Thanks in advance!