With Repti bark you may have to put quite a few holes in your tub bc I hear it holds moisture well which will cause humidity to be high. I've never personally used it but other factors in your home will be at play so you may or may not have to put a bunch of holes, the only way to know for sure is to test it. Aspen may be the best choice, you will still need to put holes but not nearly as many. You could always just use paper towels as well. No matter what you decide just make sure yout check the humdity and make adjustments so it stays around 55%-65% humidity.
Idk if you have read this or how much research you have done but the link below is the care sheet. Also check out some of the stickies in each section, there is information on different ways of setting up bps and tons of other useful threads.
http://ball-pythons.net/forums/showt...ius)-Caresheet http://ball-pythons.net/forums/showt...ius)-Caresheet
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