Thanks. Good idea
I was actually thinking about the hygeine of bladders or bottles

Last few days I put a bottle nearby on the desk and started drinking from it straight instead of using a glass, It kept me wondering if that bottle is becoming a bacteria incubator. Same applies to hydration bladders. I am not thinking about emergency situations like a quake, but regular use for hikers..etc. So, for those who use bladders or drinking bottles how do you clean them , especially they have narrow mouths.