How to Open a Nasty Pool That’s Been Neglected For Years

Written by Michael Dean
July 9, 2024

very dirty swimming pool

Whether you’ve been slacking on your pool duties or moved into a new home with an old pool, there may come a time when you’ll need to open a neglected pool. Even the idea of opening a green, swampy, and stagnate pool can be pretty daunting. Where would you even begin?

I’m here to help you open a nasty pool that’s been neglected for years. With my step-by-step process, you should be able to enjoy your sparkling, clean pool in no time!

Main Takeaways

  • To clean a pool that has been sitting for years, you’ll need to remove the debris, drain the pool, clean the pool equipment, scrub the surfaces, refill the pool, and balance the water chemistry.
  • It is possible to open a neglected pool without draining by brushing and vacuuming the pool, balancing the pool water, shocking the pool, and checking and running the filter.
  • Whether you drain or not drain the pool to clean a neglected pool depends on how nasty the pool is. If the water is salvageable, it is possible to clean the pool without draining.

Step-by-Step Process: How to Clean a Pool That Has Been Sitting for Years

It’s time to roll up your sleeves and get to work! Here’s my step-by-step process for cleaning a neglected swimming pool.

Step One: Remove the Debris

First things first, you’ll want to remove as much as possible from the pool. Use a skimmer net to get rid of any large debris from the water, such as leaves, twigs, trash, and dirt.

Step Two: Drain the Pool

If you have read my blogs before, you’ll know that I rarely recommend draining your pool completely. That said, if the pool is gross and grimy beyond repair, there’s really no point in trying to save the water already in it. You’re better off draining everything and starting from zero. So, grab a submersible pump and drain the pool completely. This will make it easier for you to look at the pool’s surfaces to see if any damage needs repair.

This is also a good opportunity to acid wash the pool surfaces. When a pool has been stagnant for a long time, the algae growth can be pretty difficult to get rid of. Acid washing is a great way to remove stubborn algae and staining.

Step Three: Clean the Pool Equipment

Over time, the nasty gunk and dirt in your pool can also make a mess in your pool equipment, not just the pool itself. So, you’ll also need to disassemble and clean the pool filter, pump, and other equipment. Replace any worn-out or damaged parts. Clean the skimmer and pump baskets thoroughly to ensure they are free of debris as well!

At this point, you may also need to check whether any of your equipment needs replacing or repairs.

Step Four: Scrub the Pool Surfaces

This is arguably the most important step. Use a pool brush to scrub the walls and floor of the pool to remove all the algae, stains, and grime. Pay extra attention to areas with significant buildup. For stubborn stains, you might need a specialized pool surface cleaner.

Step Five: Refill the Pool

Once everything is clean, it’s finally time to refill the pool with water! Depending on the size of your pool, this may take several hours.

Step Six: Balance Water Chemistry

Before jumping right into the pool, you have to make sure it’s safe to swim in by testing and balancing the water chemistry. Make sure the pool’s chemistry levels are as follows:

Step Seven: Maintain the Pool

Once you have successfully cleaned the pool and balanced the water, all you’ve got left is to maintain the pool! It’s important to establish a regular maintenance routine so you are not left with a neglected pool once again. Regular maintenance tasks include:

Step-by-Step Process: How to Open a Neglected Pool Without Draining

If you can avoid it, it’s always best not to drain your swimming pool. In some cases, you may be able to get away with not draining the pool when re-opening a gross, neglected pool. This method requires a lot of patience and hard work, but the effort will be well worth it the moment you step foot into your pool again!

Here’s my step-by-step process for opening a neglected pool without draining.

Step One: Remove the Debris

Just as with cleaning a nasty pool by draining, you start by removing the larger debris from the water. Use a skimmer net to remove any floating debris, such as leaves and twigs. You should also work the pool floors to check for debris that has sunk to the bottom. Keep working the water until you have removed 99% of the debris from the pool.

Step Two: Brush, Brush, Brush!

Just because you’re not draining your pool doesn’t mean you’re exempt from brushing. Thoroughly brush the pool walls and floor to loosen algae and grime. Don’t forget to brush all of the surfaces, and don’t forget to pay attention to the ladder and stairs. After brushing, use a pool vacuum to remove the loosened debris from the water.

Step Three: Balance the Water

Now, it’s time to test your pool water with test strips or a liquid drop test. Whatever you pick, the pool water test kit should check every aspect of the water, including the levels of pH, alkalinity, chlorine, and other chemicals. Keep the following figures in mind:

  • pH: 7.2-7.6
  • Total alkalinity: 80-120 ppm
  • Chlorine: 1-3 ppm
  • Calcium hardness: 175-275 ppm
  • Cyanuric acid: 30-40 ppm

Make sure to check and readjust daily while you are working on reopening your pool.

Step Four: Shock the Pool

When opening a neglected pool, simply balancing the water is not enough; you’ll need to shock the pool as well. Shocking the pool helps eliminate the bacteria, algae, and other nasty contaminants in the water. Follow the manufacturer’s instructions to add the right amount of chlorine shock to your pool. You can also use my handy pool shock calculator.

If the water is particularly dirty, you may need to shock your pool more than once.

Step Five: Check and Run Your Filter

After shocking the pool, you’ll need to run your filter for at least 24 to 48 hours. So, first, check your filter and ensure it is in good working condition, especially since the filter is likely clogged in a neglected pool. Then, depending on your filter type, you’ll need to clean or backwash it.

Continue to run the pool filter until the water runs clear. While filtering your pool, you may need to clean the filter halfway through if the water is particularly dirty. Clean or backwash the filter again if the pressure gauge reads around 10 lbs higher than normal.

Step Six: Use a Clarifier or Flocculant

To help your pool filter clear the dirty water, use a clarifier or flocculant to clump up the tiny particles in the water. If you use a pool clarifier, your filter will eventually clear up the clumps. But if you use a flocculant, the particles will clump up and sink to the bottom, requiring some vacuuming to remove.

Should You Drain or Not Drain When Cleaning a Neglected Pool?

To drain or not to drain… the age-old question by pool owners. When tackling a nasty, neglected pool, the decision to drain depends on a few factors. As a general rule, draining is often necessary to clean a neglected pool due to extremely murky water filled with debris, which is a breeding ground for all sorts of nasty stuff. Plus, if repairs to the pool’s surface or equipment are needed, draining the pool makes it much easier to identify and fix these issues.

On the other hand, draining a pool comes with its own risks. Most notably, it can lead to structural damage, especially in areas with a high water table, as the pool may “pop” out of the ground due to hydrostatic pressure. And that’s a much more difficult issue to solve than simply cleaning a neglected pool! Draining can also expose the pool’s surface to damage from the sun and other elements, so you’ve got to work fast.

For this reason, I recommend not draining the pool in minor cases of neglect where the water is salvageable. But if the water is incredibly murky, you may not have a choice! When choosing to drain the pool, do so slowly and, ideally, with professional help.

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Clean That Neglected Pool!

I know it can be super overwhelming when you open a nasty pool that’s been neglected for years, but the effort will be well worth it in the end. After thoroughly cleaning the pool, you can enjoy it for years to come without having to deep clean it to that extent ever again, granted you look after it properly, of course!

Do you have any more questions regarding opening a pool or pool maintenance? Let me know!

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