Another method for getting it totally dry involves propping it open and hanging upside-down with a paper towel hanging from the top through the open lid to act as a wick and speed evaporation. Another clever suggestion for cleaning that I saw recently was using a (dedicated) long-handled foam paint brush to clean the inside of the reservoir, since the narrow angled tip can easily scrub along seams.

I’ve seen a number of cleaning methods that involve different solutions – though bleach IS unquestionably one of the most fail-safe options.

Other things people use to clean bladders:
-cleaning kit tablets – effective but expensive
-baking soda solutions, especially for odors and removing plastic or bleach flavors, for which a 30-minute soak with 2 tsp should be adequate
-vinegar solutions, which are commonly used in food service for disinfecting surfaces, again about 2 tsp should be enough
-denture cleaning tablets, e.g. Efferdent, and you may want to avoid the mint-flavored ones
-foaming solutions of baking soda with vinegar or lemon/lime juice, though I’m not sure this is the best idea