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End-Of-Season Pool Repairs & Closing Guide

How to Properly Close Your Pool to keep it Safe and Clean during the Off-Season

With the hot days of summer coming to an end, you’ll soon need to start preparing your pool for the off-season.

Pool closing is an important task for pool owners. It requires that you address all issues as soon as possible so small problems don’t develop into something more severe over the winter months and pose serious, costly problems come spring.

Pool closing also means doing a thorough cleaning so you won’t end up with a green pool filled with scales and algae blooms upon opening.

The bottom line is, if you want to enjoy your pool as soon as possible next year, then take care of it sooner rather than later. The bit of extra work now will be worth it next year.

Here are the leading tips for pool repairs and properly closing your pool this fall.

Examining Your Pool

During pool closing time, check your pool for any damage. This could be cracks in the plaster or leaks that you notice from a lower pool water level. If you notice any damage, make sure to fix it with the right pool repairs before closing your pool. A small crack could become large and expensive to fix come spring, so take care of it before it becomes a serious problem.

Top Empty or Not to Empty?

It’s recommended to leave as much water as possible in your swimming pool since it will keep the pool structure intact and protect against lifting, shifting, or other damage brought on by freezing temperatures. Leaving water in your pool throughout the winter will also prevent your pool from popping out of the ground from hydrostatic pressure.

To avoid further damage to your pool, add foam in every opening (specifically the skimmer and lights) as needed so they don’t crack or damage during the winter.

If you have a vinyl liner in your pool and you are using a solid safety pool cover, make sure the water level is no lower than 12 inches from the deck. This ensures you’ve complied with your pool cover warranty.

Most established professional pool companies will use the plug system to winterize swimming pools during the offseason. How this works is by installing a one-way plug into the return of your pool that extends to the skimmer line. This allows your pool to be winterized while filled with water. This method is ideal because it will ensure your pool is structurally sound, there will be less chemical loss, it is eco-friendly, and results in fewer headaches for you come pool opening season.

What You Should Do to Prepare Your Pool for Closing

Thoroughly Clean Your Pool

Give your pool a thorough cleaning before closing it. Use a pool water skimmer to remove debris from the water’s surface. Scrub the pool walls with a pool brush attached to a telescoping pole to remove dirt and microorganisms, especially algae spores in those hard-to-reach cracks and corners.

After scrubbing, use a pool vacuum to clean dirt and debris from the pool’s floor and remove particles from the pool water. Once you’ve scrubbed and vacuumed the pool, backwash the filtration system several times and clean the filter and pump.

If you notice signs of algae blooms, consider using an algae brush as well. This breaks up algae so it can be easily vacuumed. This brush also disturbs algae so it will be more vulnerable to the treatment chemicals.

Test & Balance the Water

Balanced pool water prevents corrosion and scale buildup over the winter. Test the water chemicals and balance the water accordingly, as you would throughout the pool season. Also make sure the chlorine level is below 5 ppm so it won’t destroy other pool-closing chemicals you add.

Add Winterizing Chemicals

Winterizing chemicals help keep your pool cleaner for longer throughout the winter. These include:


Add algaecide to prevent spore growth. This is especially important to use if your pool cover has a mesh panel, and there are ways for dirt and debris to get into your pool in the off-season.

Metal Sequestrant

For those who have hard water, especially from wells, add a metal sequestrant to your pool water during closing. This will suspend metals in the water so they don’t settle on your pool surfaces, oxidize, and eventually leave stains.

Pool Enzymes

Pool enzymes help keep your pool clean in the off-season by destroying organic contaminants that enter the pool water.


Use a pool water sanitizer that is safe to leave in the pool for months. Winter sanitizers and clarifiers are meant to dissolve slowly so they can keep your pool cleaner for longer and won’t damage the pool liner.

Blow Out the Lines

You will need to blow out your pool lines to make sure no water is left to freeze and crack the pipes in winter. If you’re not sure your lines are completely dry, consider using antifreeze specifically made for pools and your climate’s cold temperatures.

Remove Pool Accessories

Uninstall and clean your pool accessories, such as ladders, rails, and automatic cleaners. Once uninstalled and cleaned, store them in a dry place for the winter.

These accessories could rust over winter and make it difficult to secure a winter cover. As a result, debris could get in your pool and you’ll end up with rusty accessories and a dirty pool come spring.

Finally, remove fittings from return lines, pull out and clean your skimmer baskets, and store your fittings in the baskets.

Shock the Water

Shock the pool water and destroy microorganisms so they don’t thrive in the water during the off-season. Add the shock treatment the night before closing so you can leave the pump running overnight to properly circulate the chemicals.

Always follow the manufacturer’s instructions for shocking a pool. These chemicals can damage vinyl pool liners if not used correctly.

Don’t forget to test the water the next day to ensure it’s balanced.

Install a Pool Cover

Safety pool covers provide maximum protection for your pool against debris and algae. It also ensures no critters get into your pool during the off-season.

For safety concerns, it is not recommended that you install a cover yourself. While you wait for the professionals to properly install your pool cover, opt for a leaf net. Leaf nets ensure that all the fallen leaves and debris are collected and don’t get into your pool.

Before the freezing temperatures arrive, remove the leaf net and dispose of the leaves and debris. It would be best if you had your safety cover or automatic pool cover installed at this point for optimal protection of your pool and safety of those in your home.

Store Pool Equipment

Keep all pool equipment stored in a warm, dry place for the winter months to protect it from the freezing cold, snow, and ice.

What You Should Avoid Doing Before Closing Your Pool

Things to avoid doing before pool closing include:

Adding Shock Directly to the Water

Since shock is usually a high concentration of chlorine, it can bleach and damage pool liners if not diluted properly first. You’ll end up needing a pool liner repair come spring if you add shock directly to the water.

Adding Shock during the Day

Since sunlight evaporates chlorine, your shock treatment won’t be effective for cleaning your pool if done during the day. So always shock your pool after the sun goes down.

Call the Experts to Do It for You

When in doubt, call the pool closing experts to inspect, repair, and close your pool properly. If pool repairs and pool closing seems like too much work to handle, the pool closing professionals will be happy to do this job for you.

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