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meh...not that big of a deal....a retailer in the business of making money isn't going to recommend products they don't sell... also, its hard enough to sell your normal chlorine/bromine systems as 90% of new hot tub shoppers think it is pure poison that makes eyes itch, skin fall off, and bleach everyone's hair white lol so the last thing I'm going to do on the sales floor is say "hey good news, you can sanitize your hot tub with the same product you clean your toilet with" oh and this other product which is straight acid is wonderful, just make sure you wear gloves and goggles because if you get it in your eye it can blind you..and yes I very well understand that bleach/liquid acid works just fine in a hot tub, just don't expect your local dealer to be on board with it
Huh...my container of muriatic acid says "for pools and spa" and I bought at a farm supply store?? I also use sodium bicarbonate (baking soda) and washing soda (laundry soap). Usually when it calls for acid it only calls for 1 tsp in 450 gallons of water; I don't know what that calculates to acid in ppm...but I still get in and my skin doesn't fall off.