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What To Do After Filling A Pool [And How Soon To Start Swimming]

You may be excited to use your freshly filled pool, but how long should you wait before swimming? You may wonder what you need to do before safely using your pool. We have thoroughly researched the available information and have found some best practices for opening your pool for summer fun.

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Once your pool is full, before treating the water, clean it using a skimmer. If you have a large pool, you may want to use a pool vacuum to get as much material out of the pool as possible. The following tasks should also be completed after you have filled your pool and before the first swim.

  • Test The Water
  • Balance The Pool Chemicals
  • Run The Pool Filter
  • Make A Pool Hygiene Plan

Getting your pool ready for use may seem like a complicated project, but we have some great tips to get you started! keep reading as we break down the steps for testing and treating your pool. We'll also address the best practices for pool hygiene so that you can make sure it stays clean, longer, and with less effort.

A small 8ft. backyard pool of a residential home, What To Do After Filling A Pool [And How Soon To Start Swimming]

How To Open A Pool For Swimming

After filling your pool, it's important to ensure it is safe for swimming. Smaller pools that you may empty and fill every few days to a week may not need to be treated but you would still benefit from a bit of chlorine. In most climates, standard above-ground and inground pools will need to be opened at the beginning of swim season.

Worker installing a handle for a pool

Click here to see a complete kit for opening your pool on Amazon.

We recommend consulting the information and recommendations provided by your pool installer or manufacturer and the instructions that come with the pool chemicals and test kits. The following are the most basic steps for getting your pool ready for swimming after it's filled.

Test The Water

Specialist testing the pool water

The four most essential levels to focus on for healthy swimming water are free chlorine, calcium hardness, ph, and total alkalinity. Pool tests can be purchased in your supermarket's garden or outdoor section or home improvement stores. They are also widely available online.

Test your pool before adding any chemicals to know your starting point, then again before you are ready to use your pool. Levels will change after you run your filter. Most pool experts recommend testing your pool water every two to three weeks.

This popular and inexpensive kit tests seven different factors. It's easy to use and will give you instant results so that you can decide what chemicals you might need and how much you would need to purchase. It also comes with an e-book to help you understand your results.

Click here to see this pool test kit on Amazon.

Balance The Pool Chemicals

After you test your water, you'll know what levels need to be adjusted. Here are some of the recommended ranges for most pools. Your water may not need to be adjusted for all levels. Most pools will need at least chlorine or another type of sanitizer added.

The Safe pH For A Pool Is Between 7.4 And 7.6

PH scale illustration

Testing pH levels is essential to indicate how acidic the water is. This will directly affect the condition of your pool lining and equipment, how comfortable the water feels, and how effective the sanitizer will be. Use water balancers such as muriatic acid or commercial products labeled as pool water balancers to increase or decrease levels.

Click here to see an example of a pool chemical balancer on Amazon.

Pool Alkalinity Range Is 100 to 150 Parts Per Million

Alkalinity measures how many alkaline substances are present in the water. It is measured in PPH or parts per million. The test results indicate how resistant the water is to ph change. The more alkaline the pool water is, the more stable it is considered to be. 

To raise total alkalinity, you can use a commercial product, but they all contain common baking soda, which can be used on its own as an inexpensive option. It is sold in packages big enough for pools.

Click here to see baking soda for pools on Amazon.

Chlorine Levels Should Be Between One And Three PPM

Specialist checking the water pH level

Chlorine is a sanitizer that inhibits the growth of bacteria. Too much chlorine can cause skin problems and burning eyes. Too little chlorine will cause cloudy water and algae growth, and allow bacteria and insects to breed in the water. For more on sanitizing your pool, read our article, 'How Much Bleach Do You Add To Your Pool?"

CYA Is Optimal In The 30 To 50 PPM Range

Since chlorine is unstable in sunlight, many experts recommend adding a pool conditioner or chlorine stabilizer known as CYA to extend the life of the chlorine in the pool water. Clorox makes test strips and has an app that can scan them to make balancing your water chemical levels easier.

Click here to see the Clorox test for stabilizers on Amazon.

Calcium Hardness Should Read Between 175 And 275 PPM

If the calcium hardness is too high, it will result in cloudy water and damage equipment over time. If the water reading is too soft, it can cause corrosion in the lining. Calcium hardness is not a concern in temporary or seasonal pools. Address hardness in permanent pools as needed; it is not a requirement to use your pool.

Bring calcium hardness down by draining and adding more water, or add a chemical called a flocculent that can clump the deposits. You can then vacuum the clumps out. Don't use this product if you have a cartridge filter, as the clumps will cause damage.

Click here to see an example of pool floc on Amazon.

Can Algaecide And Chlorine Be Added Together?

Adding algaecide simultaneously as chlorine will cause them to cancel each other out. Add each of your chemicals 30 minutes apart, making sure to run the pool filter between each item.

Always use protective gear and follow package instructions. Never mix any chemicals. This short video has more information on the best order to add your chemicals to get the right balance.

Are Pool Shock And Chlorine The Same?

Pool shock and chlorine are often sold interchangeably but have different uses. While they have the same sanitizing properties, chlorine products are intended to maintain chlorine levels over time.

Click here to see chlorine tablets on Amazon.

Pool shock, as its name implies, is to get a more immediate effect. Its chemical properties are much more concentrated and used to improve water clarity quickly.

Click here to see pool shock on Amazon.

Run The Pool Filter

A nozzle filtration under a pool

After you fill your pool and treat it, experts recommend running your pool filter for at least two hours to allow the chemicals to mix. If you have a smaller above-ground pool or only need a small amount of chlorine, the package instructions may permit swimming after only 30 minutes of running the pool filter.

Make A Pool Hygiene Plan

An often overlooked but important final step after you have retested your pool water and declared it safe for swimming is to ensure a Pool Hygiene Plan in place. You will want to make sure guests and residents alike understand and can follow it.

Planning for proper pool hygiene can include making sure there is a way for pool users to wash their feet before entering the pool or even keeping an outdoor shower handy near the pool. Pool hygiene is not only important for healthy pool water but can save time and money by lengthening the time between pool treatments.

Click here to see an example of a poolside shower on Amazon.

How Soon After Filling A Pool Can You Swim?

Pool grab handles

If you have used chemicals to balance and open your pool, you will want to consult the chemical instructions for the time frame to wait to enter the pool. Most pool balancing chemicals are safe after 30 minutes up to two hours. Cover your pool during the waiting period while the sun is out to ensure swim-ready water temperatures.

Can You Swim In A Pool Without Chemicals?

An incredibly dirty backyard pool due to lack of maintenance

If you want to use your pool one time right away without waiting to treat it, it might not cause any health issues as long as the water quality is good. It's not recommended to wait too long to put chemicals in most pools since treating your pool will ensure the water that sits will not become toxic.

An idea that has become popular in recent years is to install a natural pool. This is a pool that uses a water garden and gravel to filter and provide oxygen to the water. It may be lined like a regular pool but still appear like a pond. It's a great option for those who want to eliminate chemical exposure.

Final Thoughts

A small 8ft. backyard pool of a residential home

Now that you know what to do once you fill your pool with water and how long it might be before you can swim, pick your treatment plan and open your pool. With the proper maintenance and care, your pool can serve you as a place to relax for a long time to come!

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