How to Winterize Above-Ground and Inground Pools

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It’s that time of the year again – the leaves are changing, people are drinking pumpkin spice lattes, and you can feel winter on its way. One of the most important things to do before winter hits is to prepare your pool for what’s coming. If you don’t take care of this now, there will be a lot more work to do in spring when all those leaves start blowing around!

This guide will discuss winterizing above-ground and inground pools so they don’t freeze and burst during these cold months.

Let’s get started!

Steps to Winterize Your Pool

Step 1) Remove and Clean Pool Accessories

The first step to winterizing your pool is removing all of the pool’s accessories. Clean the skimmer, remove the ladder or ladders from the inside or outside of the pool, and then drain water out of the pool. Be sure not to leave any standing water on the solar blankets! Finally, take the time to wash off any dirt and algae before you store them.

You can store it either inside or outside of your pool house – just make sure it’s all stored safely so that nothing bad happens! If you’re storing it indoors, remember to close windows and doors so that there’s no risk of cold air blowing into your house.

Step 2) Clean the Pool Thoroughly Before Closing It

Clean the pool thoroughly before closing it. The last thing you want is for your pool to become a habitat for algae, bugs, and other nasty things over the winter! You can clean your pool with bleach or other sanitizing chemicals so that you avoid any mold or bacteria growth. After thoroughly cleaning the leaves and debris around your pool, get in there yourself and remove excess materials.

You can use a vacuum to remove leaves and debris from the bottom of your pool. You might need to clean your filter afterward or even replace it if you live in an area with high amounts of leaves on the ground.

Step 3) Balance Water Chemistry

Why do you need to balance water chemistry when winterizing your pool? To protect pool equipment and to remove sanitizers from the water. Optionally, you can use a winterizing kit, which will come with the chemicals and instructions you need to get this important step done. However, you probably don’t need it since it should be easy enough to do it yourself.

pH and Alkalinity

The pH balance in your pool should be within the range of 7.2 to 7.4., and the alkalinity should also be in the range of 80 to 120 parts per million. These adjustments should be done to avoid corrosion and other unfortunate things that could happen to your pool.

The chemical balance in your pool may need to be adjusted to maintain these levels. For the pH to alkalinity balance, the adjustments will depend on the type of sanitizer that you use.

If you use chlorine, then you will want to add sodium bicarbonate to increase alkalinity. If your pH or alkalinity is too high, you can add sodium bisulfite to decrease the pH (Increase acidity, lower alkalinity).

Calcium Hardness

The calcium hardness should be 200-300 parts per million. The concentration of calcium should be the same for both the hardness and alkalinity to maintain a proper chemical balance in your pool.

If you need to add some calcium to keep the same concentration, add calcium chloride. If you need to lower the calcium, you can add a water clarifier. Water clarifiers act as a flocculant that helps to remove calcium from the water when they are mixed with chlorine or bromine. Flocculants clump particles of algae and other contaminants together so that filters with limited filtration capabilities can filter those particles out of the pool.

Cyanuric Acid

Cyanuric acid (often called stabilizer or conditioner) is a chemical compound that reacts with chlorine and prevents the chlorine from breaking down and dissipating. It does this by forming a combined chemical reaction with chlorine molecules. You can add cyanuric acid to your pool by adding granules of stabilizer or conditioner, and then you should test the chlorine levels in your pool.


Finally, the chlorine should be between 1 and 3 PPM. You can add chlorine by using a granular or tablet-type chlorinator. You can also use chlorine tablets if you want to avoid adding any extra chemicals.

Step 4) Lower Water Level

The water level in your pool should be at least 2″ below the skimmer. If you have a saltwater pool, make sure that the water level is at least 12″ from the top of your pool. Lowering the water will make sure that no water gets into the pump during cold weather. If water gets into the pump, it has a good chance of freezing and damaging the pool equipment.

Step 5) Drain and Store Pool Equipment

It’s time to drain and store your pool equipment. You will want to drain the water from your skimmer, pump, and filters before putting any type of cover on it. Use a leaf net to remove any leaves or debris in the pool before draining the water.

If you own a leaf blower, you can use it to expel any water within the pipes. After that, you should plug the pipe openings with expansion plugs. Finally, if temperatures might drop to freezing, you should consider adding some antifreeze.

Step 6) Add Shock and Algaecide

Shock your pool with chlorine or bromine after lowering the water level. In order for the sanitizer to be effective, you’ll need to have a pH of 7.2 to 7.6, If needed, you can use muriatic acid to lower the pH of your saltwater pool.

After that, you can add 2-3 lbs. of algaecide for every 10,000 gallons of water. If you have a saltwater pool, then use 4 lbs. for every 10,000 gallons of water instead.

Step 8) (Optional) Add an In-line Chlorinator

If you want to keep your pool chlorinated during the winter, then add an in-line or drop chlorine tablets into your skimmer. The chlorine will help prevent algae growth and keep the water clean for when it is time to open up your pool again!

Step 9) Shut Off All Electrical Equipment (Lights, Pumps, Etc.)

If your pool has a light, shut it off. Also, make sure to shut off any automatic cleaners or other electrical equipment.

Step 10) Cover the Pool With a Tarp

Once you have completed all of these steps, take down your pool’s winter cover and place it on top of your pool. Make sure that it is tight enough so that there is no leakage and store it away for next summer!

Remember to cover the pump filter too! You can usually find tarps for pools at any hardware store or online. In general, thicker tarps will be more durable. If you live in an area that gets harsh winds during the winter, use two tarps.

Step 11) Store Chemicals

If you have not already, now is the time to store away your chlorine and other pool chemicals. The best way to store these chemicals is in a cool place out of reach from water or animals. Check to ensure that the seals on all containers are tight and that there are no leaks before throwing them in your pool shed or garage. Always keep your pool chemicals locked up and out of reach from children and animals!

Step 12) Disconnect Hoses and Pipes

Your last daily routine for the pool is to make sure you disconnect all hoses and pipes and plug any outlets. Make sure that any standing water is gone before sealing your pool for winter. Any water left behind could lead to damage from freezing.

Step 14) Do Not Use Your Pool Equipment Until Next Spring

If you have a saltwater pool, then the generator may need to be replaced every winter if freezing occurs. Make sure there are no leaves, dirt, or debris in the water before draining any of it. This step can help prevent algae growth.

Step 15) Above Ground Pools – Install an Air Pillow

They’re the little white pillows that you put in the pool to create a dry area around the pool’s edge. When you fill it with air, it acts as an insulator when the snow falls around your pool.

See how easy it is to prevent snow from entering your pool? That’s all there is to it! Now you can relax and enjoy playing in the snow without worrying about how it might affect your pool water.

Common Questions About Winterizing a Swimming Pool

What Chemicals Do You Put in a Pool for Winter?

There are many different chemicals that you can have in your pool during the winter. The best ones are algaecide, chlorine, and chlorinator tablets. If you have a saltwater pool, then these are also the things you’ll want to use to lower the pH levels. You can also use water treatments for specific purposes.
You don’t have to have any of these chemicals in your pool if you don’t want to. But it won’t hurt anything if you put them in there since they won’t cause any problems with the pool’s chemical balance.

How Far Down Do You Drain Your Pool for Winter?

Drain the pool to the point that the water level is just below the skimmers. This way, it will be easier for you to start up your system in the spring when it is time to open back up.

What Do I Put on Top of My Pool Before Covering?

Before putting a cover over your pool, remove any leaves or debris from the water. You can use a leaf net if needed and then cover the pool with a tarp.

What Is an In-line Chlorinator?

An in-line chlorinator is something you can buy that attaches to your skimmer, and it will automatically add chlorine into your water every few hours throughout the winter months. This way, you don’t have to worry about anything growing inside of your pool or changing the chemical balance.

What Do I Need to Avoid Putting into My Pool During the Winter Months?

When cleaning up your pool before closing it for the season, make sure you remove any large sticks or debris from the inside of it. This can cause some problems since these things won’t break down over time, and they also might damage your pump when you turn it back on in the spring.

Do I Need to Add Anything Else to My Pool During Winter?

It isn’t necessary to do any other kinds of treatments while your pool is closed for the season. You just have to make sure that you avoid adding more chemicals once everything has been put away and stored properly so they will not freeze over the winter.

What Do I Need to Store My Pool Chemicals in?

Ensure that all of your pool chemicals are stored inside a cool place and out of reach of children or other animals. You can also use containers with good seals to avoid leaks while being transported over the summer months.

When Should You Disconnect Pool Hoses and Pipes?

You should disconnect all hoses and tubes from your pool before it is time to close down for the season. This way, you can ensure that any standing water has been removed before putting a cover over it. Otherwise, there could be some algae growth during the winter months, which will cause problems when opening back up in springtime

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