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Tony- how do you measure to 3ppm......the easy way if there is one!!
The product I was referring to is spa shock xtra by spa essentials. The label reads 58% chlorine and 41% other ingredients. On the back, it says the other ingredients are clarifiers and buffers. Sounds like a bunch of fillers and a waste of money to me. I took it back. I just want to add chlorine and nothing else. It, also, said that it's not to be used as a sanitizer only a shock. I guess that's because there's only a little chlorine in there and alot of other junk.