How to Winterize an Above Ground  Pool

The warm weather is rapidly subsiding, and the swimming season is drawing to a close. Before the onset of frost, you need to take steps to protect your above-ground pool.

Wondering how to winterize your above-ground pool without draining the water? We’re covering the essential chemicals, equipment, and steps in this post.

Winterizing Chemicals

Your first task is to gather all the necessary winterizing chemicals. Without them, the water will freeze and cause significant damage to delicate components. The liner, pipes, return lines, wiring, hoses, and motor can break when water expands as it freezes into ice.

Wondering what chemicals you need to winterize an above-ground pool?

Pop by your local hardware store to pick up the following:

  • Algaecide
  • Shock treatment (chlorine or non-chlorine)
  • Stain/scale remover
  • Winterizing pill
  • Phosphate treatment

The dosage varies between products. Always read the label.

Necessary Materials and Equipment

The chemicals are only one part of the puzzle. You’ll also need an array of tools to get the job done.

If you’ve winterized your pool before, you’ve probably got these lying around the house. Otherwise, duck out and pick up the following pool equipment:

  • Pool brush (with an extension handle)
  • Pool vacuum
  • Hand siphon (or a submersible pump)
  • A 5- gallon bucket
  • A skimmer net (a leafy rake will do in a pinch)

You’ll need to gather a few materials, too:

  • Winterizing inlet plug
  • Winter pool cover
  • Air pillows
  • Chlorine, hardness, and alkalinity test kit
  • A tarp

The Winterizing Process

With your chemicals, tools, and materials at hand, you’re ready to start winterizing.

But don’t jump the gun. If you winterize too early, the chemicals will lose their efficiency before swimming season, and algae may bloom. Wait until the water stays below 65F consistently, usually around mid-October (depending on where you live). If you live somewhere warm and use your pool year-round, there’s no need to winterize.

So what’s the best way to winterize an above-ground pool?

Take the following steps to prepare for winterizing:

  1. Two weeks before you winterize, add the stain/scale remover and turn on the pump to spread it around the pool.
  2. One week before winterizing, add phosphate treatment to the pool skimmer while it’s running.

Now you’re ready to winterize:

  1. Remove any pool toys and ladders.
  2. Clean out debris on the surface with an extension skimmer.
  3. Brush the inner pool walls and floor with your pool brush.
  4. Use a pool vacuum to clean up any remaining debris on the floor.
  5. Use your testing kit to maintain the water chemistry, making adjustments if necessary.
    • Alkalinity: 80‐120 ppm
    • pH: 7.4 – 7.6.
    • Calcium Hardness: 200 – 400 ppm
  6. Add algaecide into a bucket of water and turn on the filter pump. Slowly and evenly pour the bucket into the pool around the entire perimeter. Let the pump run for two hours.
  7. With the pump still running, add shock treatment evenly around the perimeter and raise the chlorine level to 3 ppm.
  8. Let the pump run for six hours.
  9. Turn off and unplug the pump, then remove and clean the filter.
  10. Add a winterizing pill.
  11. Syphon until the pool water level is four inches below the skimmer.
  12. Replace the inlet fitting with a winterizing plug.
  13. Remove the hoses and drain the chlorine filter.
  14. Add the air pillows and tie them in place.
  15. Put the pool cover over the pool and secure it with clips.
  16. Turn off the power and water.

Your Pool Is Now Winterized

Good job. You’ve safeguarded your pool for the frigid winter months.

The only thing left to do is check for algae every few weeks, adding more algaecide as necessary.