After trying every other possible chemicals for our spa – we switched to SilkBalance over a year ago….. What a difference! Once per week maintenance, so simple to remember….. We had tried everything and the smell from the spa just permeated the air. To be honest, we were at the point where we were truly considering shutting the spa down (and after the expense of purchasing a BullFrog – this wasn’t a decision were were considering lightly!). SilkBalance saved our spa! No smell, easy to maintain, we now truly enjoy using the spa – as do all our kids and guests! Thank you!