Of all homeowner responsibilities, few so clearly indicate the end of summer as closing the swimming pool. Properly done, pool closing ensures that when you head back outdoors next summer, you will not have to complete a battery of maintenance tasks before splashing in for your first dip. Closing a pool also performs the important role of protecting your equipment from damage caused by freezing. Here's an overview of how to close a pool the right way.
You've done it all summer long, and now you must balance the chemicals in your swimming pool once more. About a week before you plan to stop using the pool, put in a phosphate remover (if you own a pool, you already know phosphates promote algae growth). Next, use the water treatments at your disposal to get the pH between 7.2 and 7.6, the alkalinity between 80 and 120 parts per million (ppm), and the calcium hardness between 180 and 200 ppm.
Even if your water is clear, introduce a superchlorinating powder, known as shock, designed for pool closings; it should contain at least 65 percent sodium hypochlorite. For use, consult the directions listed on the packaging of the shock you buy. Typically, a one-pound bag is appropriate for 10,000 gallons of water. Mix the product with some pool water in a large bucket, then as the filter is running, pour the mixture into the pool.
Wait until the total chlorine level returns to a range between 1 and 3 ppm (it should take a few days). Next, add an algaecide as a further measure to keep those tiny, green pool-tinters at bay through the cold months. Again, choose a product designed for pool closings. How much should be added to the volume of water your pool contains? The amount varies; follow the instructions provided by the algaecide manufacturer.
A pool closing kit includes all the chemicals you might need to stabilize the water chemistry of your pool. Buying the kit might be less expensive than buying everything separately. Shop around online or check prices at your local pool supply store.
Vacuum the pool with the goal of making it even cleaner than usual. Scrub the sides if mold or grime has built up. Remember also to remove any debris with a handheld skimmer. If you have a sand filter, backwash it to discourage algae growth. If you have a removable filter, take it out and clean it thoroughly.
For an in-ground pool, run your filter or use a siphon pump to bring the water level down to a height beneath that of the skimmer door. For an above-ground pool, simply remove the outlet hose from the skimmer basket.
Because residual water can freeze inside your pool equipment and water lines, they must be as dry as possible to avoid wintertime damage. It may be necessary to blow out the lines with a shop vac. Should doing so prove impossible (or deeply inconvenient), you can head off ice-related problems with a swimming pool antifreeze. The draining process is easier for above-ground pools: Take off all the hoses and remove the plug from the bottom of the filter.
Owners of above-ground pools are advised to make use of a pool pillow. Placed in the center of the pool and tied to its sides, these air-filled rings help prevent water in the pool basin from freezing. For in-ground pools, this precaution is recommended only if you live in an area with especially harsh winters.
Store ladders, diving boards, and other peripherals in a clean, dry place before stretching your pool cover into position. So long as the cover remains in place through the worst of the winter's storms, the water in your pool should be mostly clear the next time that you see it.