Pool opening checklist

If the pool was covered, pump standing water off the cover before you pull it. A cover full of water is heavy enough to damage the cover and the coping. Clean the cover, let it dry, and store it out of the sun if you can. Pools that run all year can skip this step.

Set the water at the middle of the skimmer opening. Low water is the most common reason a pump sucks air on the first start. Walk the deck and look for cracked return fittings, loose handrail anchors, and skimmer lids that no longer sit flush. Those parts are in fixtures and plumbing.

Open the valves that were closed for winter, or confirm they are already open on a pool that never closed. Check the pump lid o-ring, empty both baskets, and prime the pot if the lid is above the water line. Start the pump and watch the lid. A steady stream of bubbles means air on the suction side. The usual causes are in why a pool pump loses prime.

Clean the filter before you judge the water. A dirty filter on opening day makes a clear pool look like a chemistry failure. Cartridge, sand, and DE each have their own steps in how to clean a pool filter.

Test before you treat. A pool that sat covered can be low on sanitizer and high or low on pH at the same time. Balance alkalinity, then pH, then sanitizer, and wait between doses. The sequence is in how to balance pool water.

Test the light GFCI with its button, then switch the light on. If the GFCI trips and stays tripped, leave the breaker off and call an electrician. Do not open the niche. What you can check safely is in a pool light is out.