What Do You Do After an Above Ground Pool Is Filled With Water?

Hunker may earn compensation through affiliate links in this story.
Chemicals must be added to the pool prior to use.

The filter is connected, and you've waited more than a day for your above-ground pool to fill. Now the time has come to go swimming. Not so fast...there are a few things you need to do before to taking your first official dip. They include cleaning the bottom of the pool and testing the filter, along with adding chemicals to adjust the pH, free chlorine concentration, total alkalinity, water hardness and cyanuric acid concentration.

Prepare the Filter

Check the hoses, and inspect them for any leaks. Turn on your filter, and begin the circulation process of the water. Depending on the type of filter you are using, ensure the filtration system is completely set up. Cartridge filters must have a filtration cartridge inserted prior to use; the sand filter must be filled with the sand; diatomaceous earth filters must have DE powder added through the skimmer.

Any filter not properly set up can cause damage to the filter system. Get to know the employees of your local pool supply store. They are usually willing to answer any questions you have and can help you get acquainted with your system by giving you useful tips.

Vacuum the Pool Bottom

After installing the pool and filling it will water, there may be small particles of sand and pebbles left over from the pool installation. Prior to use, vacuum the pool to ensure the bottom is clean and free of dirt and sharp pebbles that can potentially cut the pool liner or your feet. The sediment on the bottom may include algae and bacteria that protect themselves by clinging to the pool liner. Vacuuming removes these organisms and prevents them from establishing colonies.

Adjust the pH

Before you add chlorine to the pool, you need to adjust the pH to a value between 7.2 and 7.6. If it's higher, the chlorine won't work well, and if it's lower, the pool water will be uncomfortable on your skin. Chlorine affects water acidity, so it's important to adjust the pH again after adding chlorine. Use sodium disulphate or muriatic acid to lower the pH and baking soda or soda ash to raise it. Follow the dosage instructions on the chemical container; the amount you need depends on the value of the pH before you add the chemicals and the volume of your pool. Dilute acids in water before pouring them into the pool, and run the circulation pump for two to three hours to disperse the chemicals you add.

Shock the Water

Most pool owners sanitize with chlorine, and if you're one of them, you'll want to maintain a chlorine concentration between 1 and 3 parts per million. When the pool water is fresh, it's a great idea to shock it by bringing the chlorine level to 10 ppm or more. This kills any bacteria or algae that have already become established. Calcium hypochlorite quickly releases free chlorine into the water and is the best product for shocking. Follow the instructions on the container to make sure you add enough. Because this product can be harsh for swimmers, it's best to revert to sodium hypochlorite (pool chlorine or bleach) for routine sanitizing.

Chlorine Alternatives: If you don't want to be one of the pool owners who sanitizes with chlorine, you can use bromine -- a similar chemical -- or a nonchlorine sanitizer. If you opt for a non-chlorine product, you shouldn't mix it with conventional pool chemicals. Check the instructions for the products you can use in conjunction with it.

Cyanuric Acid: Chlorine swiftly degrades in sunlight. To prevent this, you should add cyanuric acid, which is a stabilizer. If you do this when the water is fresh, you shouldn't have to add more for the rest of the season. The optimum CYA concentration is between 30 and 50 ppm. Dichlor tablets contain this stabilizer, so using them to raise chlorine levels kills two bacteria with one stone.

Balance the Chemicals

When you wake the morning after shocking, your pool you will already show a noticeable difference. Use test strips to check the water for chlorine, pH and alkalinity, and adjust each level accordingly. The water is safe for swimming when you get the following readings:

  • pH:

    7.2 to 7.6

  • Alkalinity: 80 to 120 ppm

  • Calcium hardness: 100 to 400 ppm

  • Chlorine: 1 to 3 ppm

  • Cyanuric Acid: 30 to 50 ppm.

If you need to adjust any of these, the instructions on the product will tell you a specific amount of the particular chemical to add, based on the capacity of your pool.

Nicholas Briano

Living in New York City, Nicholas Briano has been a professional journalist since 2002. He writes for "The Wave," a community weekly covering the borough of Queens. Briano holds a Bachelor of Arts in journalism from Brooklyn College.