I love Hammer Heed but made the same mistake and left it in the camelbak too long. I couldn't get rid of the mold so tossed my bag out. I only use the Heed in my polar bottle and wash it very well afterwards. The Heed has come in real handy since we have the heat and humidity in our area. The best thing to do is to put a ziploc bag of additional Heed in your camelbak pocket and fill a water bottle with it as needed.