My new bong got mold after 4-5 days of daily use. I left water in it for up to 7 hours then emptied it and left it over my dehumidifier to make sure it stayed dry. After 4-5 days I found white powder that looked like white mold. Just gave it the old isopropyl shake with salt and it looks clean but I'm afraid of it coming back. How do I keep my bong from getting moldy? Most people i know have disgusting, wet bongs for weeks that don't grow mold I don't know what I'm doing wrong.
Pics would be helpful so we can see if it's actually mold. Also are you in a very humid area? If not that definitely makes it even less likely to be mold. Perhaps leaving it on top of the dehumidifier is sucking tons of humidity into it? If it truly is mold I have to imagine that's probably why.
I've been smoking for 30+ years and until very recently I have always been horribly negligent when it comes to cleaning my rigs. I have never seen mold in a bong. I would suspect the dehumidifier.