BioGuard Freshen Up Swimming Pool Water Purifier - 7lb BioGuard Freshen Up Pool Water Purifier Destroys unwanted contaminants in your swimming pool Sweat, sunscreen, pet dander & lawn fertilizers don't stand up against the intense fizzing action of BioGuard's Freshen Up Get your swimming pool water cleaner, clearer and fresher in as little as 15 minutes 7lbs treats up to 30,000 gallons of pool water!