
I have heard so many things:
1. Fill it halfway with water and microwave it until the water gets hot (but not too hot to boil).
2. Using Camelpack hydration cleaning tablets
3. Baking Soda - Bicarbonate of Soda (Mix baking soda with water and allow it to soak in the bladder - anywhere from an hour to overnight. If you are getting ready to use it the next day, it's best to allow it to dry overnight. How much baking soda? I've seen recommendations from 2 tablespoons to half a cup, mixed with hot water to help it dissolve. After it soaks, rinse thoroughly with warm water.)
4. Baking Soda and Lemon or Lime Juice (This combination is also recommended, but be warned that it produces a foaming action. Mix a couple of tablespoons of baking soda in a couple of cups of water, put it into the hydration bladder. Now add a similar amount of lemon juice or lime juice and be prepared for the bubbling. Allow that to sit for 30 minutes to overnight and rinse thoroughly with warm water.)
5. Denture Cleaning Tablets (Drop them into water in the pack and allow it to work for 15 minutes as they recommend for dentures. Rinse thoroughly. Some recommend not getting the ones with mint flavor unless you want your water to always taste minty fresh.)
6. Baking Soda and Vinegar (Fill the bladder, add 1 tablespoon of vinegar and shake it, then add 1 tablespoon baking powder then shake it. Now drain and rinse thoroughly. This is reported to be good to remove the chlorine taste after bleaching the bladder.)
7. Bleach Solution (Add a capful or teaspoon of bleach to enough water to fill the reservoir. Allow to bleach for an hour to overnight. Rinse very thoroughly with 4 or more changes of water. I would recommend then following that with the baking soda and lemon juice or vinegar to help remove the bleach flavor. But this is the best way to kill fungus and bacteria, especially if you see visible growth.)
8. Water and a brush only
9. Leave out in the sun
The ideas go on and on. I wonder which you think is best because (1) it has the least problems with taste lingering in the bladder and (2) killing any bacteria in the reservoir, tube and mouthpiece. I have one of my bladders that actually has this slimy film building up, so it's probably time
