ScumBuster 2-Pack Hot Tub Spa Water Clarifier - 2 x Quart Bottles (64 oz. total) Two Quart Bottles Earth Friendly Formula - no harsh chemicals Prevents tub rings & inanimate scum formation - will not affect pH Economical: Use only 1/2 oz. per 100 gallons per week 2- pack. STOCK UP & SAVE!!