We have been using Nature’s Hot Tub Treatment for 7+ years with great success even though we have really hard water and struggled with chemicals in the past. Four years ago we had a baby and stopped using the hot tub and left it with it’s original water and the lid on without any use. Now, four years later without any attention on our part, we found the water in the hot tub to still be clear and without smell! We are very happy to have a natural hot tub to soak in without the smell and itchy skin of using chemicals. This system is very easy to use.