Product review (5 stars): Does exactly what it says!
Ive had this for about a month now and it does exactly what it says it does! i have a large 10 gal wick humidifier and was really sick of the nasty filters, and the cleaning out every month. After spending an hour cleaning the pan, fan, and water containers with bleach i thought i needed to do something. I found this on amazon and based on reviews i purchased it.

well one month later, no smell, no mildew or algae, and its clean as it was the day i finished cleaning it. I also don't use anywhere near the recommended amount - i use maybe a splash in each 4 gallon container on each fill up. The wick seems to be lasting much longer than without this. I am purchasing another bottle today to make sure i don't run out!