Maintain a clean, safe pool with the Kem-Tek Shock Quick 15,000 Gallons 10-pk. A must for your DIY pool maintenance program, Shock Quick "shocks" the pool with high doses of sanitizers that rid the water of unwanted contaminants. Use this Kem-Tek product if your chlorine test readings keep dropping, a chlorine odor emanates from your water or if there are visible signs of algae. Each pouch treats 15,000 gallons of water.