What Chemicals Do I Use When I Open a Pool for the First Time?

Filter Preparation

The filter keeps your water clean of any small debris and dirt that can affect the chemicals. Add two quarts of earth to your filter through the skimmer while it is running before adding any chemicals. Let the filter run with the earth for a few hours to get the water in the pool circulating. Think of this activity as if you are preparing the water for the chemicals.

Add one gallon of shock treatment for every 5,500 gallons of pool water. Shock is usually sold in a powder form that must be diluted. Shock sold as prepackaged liquid by the gallon is slightly more expensive, but also hassle-free. Pour the shock around the perimeter of the pool's water, directly on the surface. Never add shock through the skimmer--it's not as effective. Let the filter run for 24 hours after adding the shock. You should see a marked difference in the water the following day.

Use test strips purchased at a pool supply store to test the chlorine levels in the pool. The chlorine levels will be elevated slightly after a shock treatment. To start, add two cups of chlorine to the surface for every 5,500 gallons of water. Let the filter run for a few hours, then test again and add more chlorine if necessary until the test strips reads in the "normal" range.

The pH and alkalinity chemicals only have to be added if the same test strips used for the chlorine shows that these levels are not within normal ranges. The chemicals you should have on hand as a pool owner are pH increase and pH decrease chemicals. The same goes for alkalinity increase and decrease products. Add these chemicals as necessary. Doses are measured as per every 5,500 gallons of water. Follow each product's specific directions and add any of these four chemicals through the filter's skimmer.