Yes some people rave about it on amazon , I used it when I first filled my new hot tube( I never owed a hot tub before ) in January , so I didnt experience the water yet without it , but it only lasts 3 months and we are passing the 3 month mark now . I went to the pool dealership last night to test my water to see if it needs changing , the TDS read 1000 , so ill change the water in a few weeks . I asked about it and they said im on the " Spa Marvel Program " I thought hmmm , but my husband goes for anything sold and wants it , but I think its not nessasarry . My combined clhorine was high 1.73 ppm , im using spa boss chlor-aid and non chlorine shock . I shock everytime I put chlorine in about 25g of each every 3 days or so , but because of the high CC I had to put 60 g of non clhorine shock to lower it , she said to shock everytime I use the hot tub . Im wondering if I dont need to shock then after I put clhorine in ? Im wondering why my CC was high if it was because im not using enough shock ?. I have a Sundance with a clearray water purification system . I need to get a test kit , my test strip showed hardly any chlorine and when she tested it , it showed 2.05 ppm FC and TC 3.78 ppm , and im to be in the 1-3 ppm range , the test strip wasnt registeing any chlorine .
