I have a similar situation, but scale is my prominent concern. My pool supply shop doesn't carry Jack's products, but does have a product by "Azure" that is a stain and scale remover. The active ingredients are different than Jack's purple stuff. The MSDS lists the main ingredient for the azure product as Tetrasodium salt of Ethylenediaminetetraacitic acid. Neither the MSDS nor the package address salt water pools or whether I need to bypass the heater. Would this address stains or scale without damaging the equipment or water? Can I use it or should I take it back?