How to Open an Above Ground Pool After Winter

Temperatures are rising, and it’s time to open your pool after the winter. But how is the pool properly wintered out in spring?

First, the pool cover is removed, and the coarse dirt is pulled from the pool with a net and a pool vacuum. The water is then pumped out of the pool, and the pool is scrubbed with pool cleaners. Afterward, the pool can be filled again and treated accordingly with chlorine.

In this article, you will find practical tips on how to open a pool in spring and which care products are necessary.

How to clean the pool after winter?

It doesn’t matter whether you want to clean a concrete pool, an Intex pool, or another above-ground pool after the winter.

The steps shown here to clean a pool can be used universally for any swimming pool.

What do you need to bring a pool in spring?

  • The sand filter system or alternatively a submersible pump to empty the pool.
  • Compatible alkaline pool cleaning agents against stubborn deposits like algae.
  • Pool brush or a suitable sponge to scrub.
  • As an alternative, a garden hose or a high-pressure cleaner.
  • Pool chemicals such as chlorine granulate and algaecide for water treatment.
  • A pH reducer and pH increaser for pool maintenance.

In the following chapters, I will describe the products in more detail and give you precise recommendations.

Important information to avoid damage to the pool:

  • Only use certified pool cleaners for pool care and avoid household remedies such as vinegar.
  • Do not use any sharp or pointed tools to damage the pool liner.
  • Also, avoid steel wool or wire brushes, as these can also damage the liner in the pool.

In the next chapter, I describe how to clean a pool after winter.

1. Remove the pool cover

Before we actually start cleaning the pool, the first thing to do is remove the pool cover.

Before doing this, you should scoop off excess water that has collected on the tarpaulin with a bucket or (if available) briefly pump it off with a pump.

Leaves and other dirt are swept from the pool cover with a brush to not fall into the pool.

The pool cover can then be removed.

Briefly clean the dirty pool cover and stow it dry – so the cover can be used again in autumn when the pool is wintered.

Finally, remove the air cushions or pressure cushions from the pool.

2. Roughly clean the pool basin after the winter

In the second step, the pool basin is roughly cleaned of impurities.

Most of the time, despite the pool cover, plenty of leaves and insects got in the pool – this is normal.

Take a pool net and drive it through it to remove all visible foreign matter.

This step is important so that the submersible pump or the sand filter does not clog the first time you use them.

Tip: In addition to the net, you can use an electric pool robot or a pool vacuum to get rid of the dirt in the pool.

3. Drain the pool water

A complete pool water change is recommended in spring if you have used a hibernating agent.

Before draining the pool water in the next step, the water is circulated for 10 to 15 minutes with the filter system. Then the sand filter system is backwashed with subsequent rinsing.

This process removes the organic debris from the corners of the pool.

You must never do a backwash beforehand!

The pool water can be drained after the rough dirt has been removed.

It is best to use a submersible pump for emptying.

The following points should be followed when draining the pool:

  • Water that has been treated with chlorine is allowed to seep into the ground. If overwintering agents, algaecides, or other biocidal chemicals have been used, don’t pour the water into the ground.
  • There is a risk of flooding if you drain the pool water on your own property.

I recommend that you ask the local authority how to treat the pool water for the reasons mentioned.

Avoid trickling the pool water on your own property, and do not water plants or fruit trees with the contaminated water.

Tip: Under no circumstances, heavily chemically treated pool water should not be drained without consulting the authorities.

4. Checking the pool after winter for damages

Once the pool water has been drained, the pool can be checked for any damage.

To do this, check all visible lines and the multi-valve of the pool system.

After a harsh winter and incorrect preparation, damages may have occurred.

To not experience any nasty surprises, you should briefly press the trigger – sometimes, a listening test also helps.

Also, look at the floor and walls to see if there are any cracks or leaks.

Tip: A foil repair set can quickly repair small cracks in a foil pool. If significant renovation work is pending, you are well-advised to hire a specialized company.

5. Basic pool cleaning after the winter

All surfaces in the pool should be cleaned thoroughly with a suitable pool brush, sponge, or high-pressure cleaner.

Cleaning the pool prevents algae and other germs from spreading further after being filled.

Before using an algae agent, the limescale deposits in the pool should be removed with an acidic pool cleaner.

I recommend the following acidic pool cleaner.

  1. Rub the chemical on all pool areas.
  2. Let the remedy sit for 5 to 10 minutes.
  3. Rub one last time and then rinse with clean water.

Black algae, which are harmful to health, settle in the joints and have to be removed.

I advise you not to use home remedies for pool cleaning, and I recommend this algae destroyer available at a reasonable price.

The recommended agent also serves as a preventive anti-algae agent.

Tip: Note that acidic cleaning agents can be used for plastics, damaging sensitive surfaces such as marble.

If you are using a pressure washer, make sure that the pressure is not too intense. Use a large jet to avoid damaging the pool.

6. Prepare the pool before filling it in spring

After the basic pool maintenance, follow these steps:

  1. Spread the anti-algae agent over the entire pool area.
  2. Then assemble all components for the water treatment in the pool.
  3. Check the skimmer, the filter system, the plugs, and the seals.
  4. A new filter is used for a cartridge filter.
  5. Close all open-drain taps and open the ball valve of the floor nozzle with a quarter turn.
  6. Check the Fi switch by briefly pressing the release button.

If necessary, the sand in the sand filter system must be replaced (every 1 – 2 years).

For cleaning and disinfecting the filter sand, you can use the chlorine granules – regular use is recommended.

Calcification of the sand in the sand filter system can be recognized by large, hard chunks. This calcification can be removed with a decalcifying agent for filters.

If everything is done so far, the pool can then be filled.

7. Fill the pool with water

You have the freedom to choose how you refill your pool with water.

  • Well water: If you use well water, I recommend using an anti-calcium chemical to prevent discoloration. Furthermore, it prevents lime.
  • Tap water: Use an anti-calcium agent here as well while filling.

In addition to filling with well water or tap water, there is also the option of having the pool water delivered by a supplier.

Check the delivered water for its pH value, calcium hardness, and total alkalinity.

There was one situation when contaminated pool water with black algae was delivered.

Open your eyes and test the water!

You should occasionally check the flanges and lines for leaks during the filling process.

The filter pump is then backwashed for approx. 5 minutes and rinsed for 1 minute so that the remaining contaminants are also flushed out of the pool.

Leave the manual vent open until water emerges and a stable water cycle of 0.3 bar has been created.

8. How to treat pool water after winter

First, check the running times of the pump and set the automatic timer.

The water should be circulated 2 to 3 times within 6 to 8 hours a day.

You can roughly calculate how long the pump should run using this formula.

Operating time in hours = (2 x water volume of the pool in m³) / pump flow rate in m³/h.

The following parameters should be set beforehand as follows:

The following means are helpful to adjust the pH value: A pH plus or a pH minus.

Over the next 14 days, these parameters ​​are checked daily using a water tester and improved if necessary.

If the pH level is correct, you should shock your water in the pool – use chlorine granules or bleach for this.

It is important that the water temperature during a pool shock is above 59 °F and the chlorine content has a level of 3 – 5 ppm.

Then let the filter system run through for 48 hours.

The chlorine content should have reduced mainly over time and ideally have a value of 0.6 to 1.5 ppm – if necessary, let the pump run longer.

Then you go to the usual pool maintenance with chlorine and active oxygen.

Tip: You can also use a flocculant in the pool later.


Your pool is now officially cleaned and awakened from hibernation.

When it is time to clean the pool after winter?

The most important pool cleaning is after winter. But when exactly should the pool be cleaned in spring?

Advisors recommend cleaning the pool after the winter only from a water temperature of 54 °F, and others advise only wintering the pool from a water temperature of 59 °F.

But that would be sometime at the end of May and be a short pool season if you don’t heat your pool.

So when is the right time to clean the pool after the winter?

Most pool owners start cleaning the outdoor pool in late March or mid-April – this is not a problem with appropriate pool heating.

As a rule, it takes about 2 weeks to clean a swimming pool after winter, and if you start in April, you are well in time to start the new pool season.

In addition, when to clean your pool after the winter depends heavily on the geographic location.

Pool owners in the south usually start removing the traces of winter in the pool a little earlier.

Conclusion on how to clean a pool in spring

The best time to clean the pool is in spring, but cleaning the pool after winter is time-consuming and requires perseverance and patience.

All you have to do is get the accumulated dirt out of the pool with a net and a pool vacuum, scrub the pool with a suitable brush and pump off the old water.

The pool is then filled up, and the water is treated with chemical care products such as pH-Plus, pH-Minus, and chlorine granulate.

As you can see, it’s no big deal to clean the pool before the new pool season.

If the pool is cleaned properly, the subsequent pool maintenance in summer is a matter of habit – in the end, you have less stress and benefit from clean pool water.

Warning: take a close look at which chemical pool cleaners you are buying.

Many algaecides are based on copper sulfate, which is considered harmful to health. The agent can also cause stains on PVC liner pools.

If the hair discolors while swimming in your pool, it is probably due to the algaecide.

Algae can be avoided by regular pool cleaning with a pool vacuum, and you do not necessarily have to use an algaecide.

Do you have any other questions about how to clean a pool after winter?

Contact me at @contactswimfool on Twitter, Facebook, or YouTube – I’ll be happy to help you personally.

Have fun cleaning your swimming pool!

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Hi. I'm Max Berg. I've been in the pool industry since 2015 and have always felt drawn to water. I'm the author behind, where I share my years of experience in pool maintenance and give helpful tips on keeping a swimming pool or hot tub clean. My tips reduce the costs of water treatment and protect the environment.

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