Don't drain your above-ground pool all the way

Winterizing your above-ground pool is a half-day job, and the most important rule is to drain it partway, not empty.

Start by scrubbing the walls and floor and vacuuming out the junk. Then balance the water — alkalinity, pH, and calcium — before you add the winter chemicals. If you put winter chemicals in dirty water, they’ll just fight the algae and lose.

Lower the water level to about 4–6 inches below the skimmer mouth. Most above-ground pools need some water left in them to hold the liner in place and handle ground pressure. Leaving the pool completely empty is how you end up with a wrinkled liner or a collapsed wall.

Next, drain the pump, filter, and hoses. Loosen drain plugs, store them in the pump basket so you don’t lose them, and blow out or tilt the lines to get the water out. Then add your winterizing chemicals, float a small air pillow in the middle of the pool, and pull a winter cover tight over the top. Clip or cable it down hard — a flapping cover will shred itself in the first windstorm.

If your area gets cold enough to freeze, don’t skip the air pillow or the chemical kit. Both are cheap insurance. Also, make a note to check the cover a few times through winter and sweep off heavy snow, because the cover will