BioGuard SoftSwim C Pool Clarifier Biguanide- Case of 2 Gallons 15 out of 5 Stars. 1 reviews hth Ultimate shock treatment, 1 lb Add $18.99current price $18.99hth Ultimate shock treatment, 1 lb 125 out of 5 Stars. 12 reviews Pristine Blue Pristine Extra Shock for Pools and Spas 6 ...