Clean Start is a spa purge for your spa plumbing. Before your first time ever using Silk Balance, you will use Clean Start to cleanse organic deposits, dirt, soil and inanimate organic particulates from plumbing systems. This is the only purge product that will not create foaming residue that requires multiple flushes to remove. It will leave your spa with a fresh and clean scent. The day before draining your hot tub, you mix Clean Start with water, pour it in your hot tub and let it circulate for 10 minutes, then let stand overnight. Next day, drain your hot tub and begin your Silk Balance regimen.