Things You'll Need
pH test kit
pH up or soda ash
pH down or muriatic acid
Chlorine test kit
Algaecide is a part of a pool sanitation schedule that protects swimmers from harmful organisms. Used properly, it makes the pool water safer for swimming and causes no harm. Use a chlorine shock product to kill algae and an algaecide to prevent reinfestation. For best results, add algaecide in the morning on a sunny day to increase algae uptake during peak growth periods.
Use a pH test kit according to label directions to check the pH of the pool water. Adjust the pH by adding acid or pH down if the pH is above 7.6. Add soda ash or pH up if the pH reading is below 7.4.
Add the algaecide around the outside edge of the pool. Turn on the pool pump and circulate the water for one hour.
Run the pH test again. Readjust the pH if necessary to bring it into the 7.4 to 7.6 range. Circulate the water for one hour after adding chemicals.
Test the chlorine levels. The pool is ready for swimming once the chlorine drops below 3 ppm. Maintain the chlorine levels between 1 and 3 ppm to prevent algae regrowth.
Use a chlorine shock product to kill algae. Add algaecide to prevent regrowth.