Why is my pool cloudy? is one of the most-asked questions asked by pool owners. Nobody likes swimming in a cloudy pool! There are several causes that can contribute to having a cloudy pool – luckily, there is almost always a relatively easy fix.

Causes for cloudy pools can vary, from the very simple issue of the pH level being incorrect and imbalanced, right through to the pool filter and plumbing system not working properly.

To answer the question “why is my pool cloudy?”. Let’s work through each one so that you can tick it off as we go, and quickly and easily find the answer – and the solution you need to make your pool water sparkling clear again.

Why is your pool cloudy? Because your filter isn’t running properly.

Ensure your pool filter is running regularly and well. Filters can be the first thing to ‘go wrong’ with your plumbing system – if it’s not running, stopped running suddenly or isn’t running often enough, this is usually the cause of cloudy water, algae formation, and those vile oil slicks.

Normally, your filter should be running at least eight hours a day – try running it for 10 or 12 hours if it’s already running for those eight hours.

If it’s not working as it should be, your filter might need backwashing. Periodically, the filter system needs to be backwashed to remove debris that may be clogging it up. Debris creeps in from your water.

If your filter isn’t working properly, you might want to check your sand to see if it has any issues. Pool filter sand often becomes blocked, containing small blobs of oil and debris, or it may become channeled, which is when the sand has holes in it and so the water is flowing through these holes without actually being cleaned.

In hard water areas, the water and sand can “calcify” with calcium deposits, toughening the sand and turning into actual sandstone.

Use of particular chemicals can clump and block up the filter so it needs cleaning every year to prevent this.  High amounts of sunscreen and other oils can also cause blockages in the sand.

You may also need to wash your cartridge filter. You’ll need to thoroughly wash these and if they don’t get washed they get blocked up super fast. Luckily, you only have to do it once or twice a year, but because it’s so infrequent it’s easy to forget. Miss it, and you’ll end up with that cloudy water for sure!

Why is my pool cloudy? Because your whole circulation, pump, and filter system aren’t working properly.

Check for leaks, cracks, dirt, and grime, in all of your circulation, pump and filter system, and that everything is working as it should be.

Why is my pool cloudy? Because your ph is too high or too low.

Improper pH can cause cloudiness. Alkalinity that is too high is especially likely to cause cloudiness!

The Damage Caused When You Raise Your pH Levels Too Much!

Although this article concentrates on how to raise your pH levels in your swimming pool, and an acidic pool sounds nastier than an alkaline pool, the damage can be just as great to your health, water, equipment, and deck if you go too high up the pH scale.

Your eyes will still sting and be itchy, and you’ll still experience itching, irritated skin.

In addition, you’ll also potentially experience a kind of ‘scale’ forming, which blocks pipes, filters, pool walls. A bit like limescale in your kettle/bathtub.

It can clog your filters if you use a sand filter and causes those ‘holes’ in the sand element where sand clumps together and as a result forms hole elsewhere, as well as blocking up your sand with clumps of grime that attaches to the scale build-up.

Ultimately the water can’t filter properly through your sand filtration system and your pool quickly gets even cloudier and less hygienic.

All this can be prevented when you know how to raise the ph levels of your pool safely.

Is pH the reason why is my pool cloudy?

This is the test that will tell you if your pH levels are the reason your pool water is cloudy.

The first thing you need to know about the process of how to raise your ph levels of your swimming pool is that the easiest way to take a pH reading is by using those little papers we talked about, pH paper!

NOTE – this is not the same as litmus paper, which is the stuff you used to use in school and they only tell you whether your water is acidic or alkaline, not provide you with the actual reading of the pH level.

You want to get your hands on pH papers! They are so simple to use and cheap to purchase. Simply scoop a cup of your pool water out into a container, and simply insert your paper into the cup. Watch for the color to change, and then hold your strip next to the test paper scale that came along with your papers when you purchased. Match the color to the scale, which will give you your pH reading. Simple!

However, there is a more accurate way to gain a pH reading, by using a pH meter. They are more expensive and slightly trickier to use, however, they do provide a much more accurate reading which is highly important if you want to be super accurate in deciding whether or not to raise the pH levels of your pool.

To use a pH meter you have to take the water temperature first as it impacts the reading due to how sensitive it is! Use a thermometer to take a reading of the water temperature in your cup – note this must be done as soon as your water leaves the pool as even a slight shift (for example your cup left on the deck in sunlight while you go to fetch your thermometer)! will change the reading and make it inaccurate.

Input the temperature into your pH meter, and then insert the probe on the meter into your water. Your pH reader should then tell you the exact pH level of your water.

Anything over 7.8 means your water level is too alkaline, which could be the major reason you’re experiencing cloudy water!

If the pH is high, pH Down is used to bring your pH levels into normal rates. pH Down comes in two forms: liquid acid (muriatic acid) or dry acid (sodium bisulfate). Follow the instructions carefully, keep testing your pH levels as you do so and watch you cloudy water vanish!

Why Is My Pool Cloudy? You haven’t used enough sanitizer.

Check chlorine or bromine levels regularly to make sure they are at the correct level. If they’re not high enough, algae growth may cause cloudiness, and so can that film that suntan oils, creams, and lotions leave behind.

Check your chlorine levels. You are aiming for a concentration of between 1ppm – 3ppm. If you have 1ppm or less, you could end up with cloudy water and your system not working properly.

Why Is My Pool Cloudy? It’s been raining!

Yes, even a dose of good old rain can not only spoil our pool fun but can actually make our pool water cloudy. It can imbalance the chemicals in our pool that were measured for a pool with less water in it, leaving the pH imbalanced too – especially if there was stormy weather and leaves and debris were blown in!

You have several options here – clean the pool first and then add in more of your preferred sanitizer, and / or wait for the pool to drop back to normal levels, which may take a day or two, or even more depending on the weather – and then recleaning and taking the pH levels again.

We recommend waiting until the pool water drops to its normal level – you can always drain your pool slightly but this can be a bit labor-intensive. But the good news is once the rainwater has gone and the debris the storm took into your pool has been cleared with the help of a little pool shock, your pH levels should return to normal and your pool will be bright and sparkling clean to swim in again!

Why Is My Pool Cloudy? You’re not balancing the biguanide!

Do you use biguanide as your primary pool cleaning solution? It’s notoriously more difficult to balance than chlorine, not just to balance but to maintain the balance! Make sure you keep checking your pH levels if this is your chosen sanitizer to prevent cloudiness, but if you’re seeing cloudy water this could be the reason why.

Give your pH levels a check and see, and rebalance those levels back to the 7.5 point or thereabouts!

Why Is My Pool Cloudy? I still have no idea!

These checks and fixes still aren’t working? Still noticing a film of oil or cloudy patches in your water? Well, let’s look on the bright side. At least you’ve noticed, and can’t prevent the problem from getting worse! Now comes a simple fix:

Use A Pool Clarifier To Treat Cloudy Water

If you still aren’t sure what the answer is to the question ‘why is my pool cloudy’ try this fix here if you’ve tried everything suggested above. A pool clarifier will have your water looking clearer in no time!

Different types of clarifiers may carry slightly different instructions, but most work with the following procedure:

  • Run your swimming pool filter system for 24 to 48 hours. If the pool is still cloudy, then continue with the next step.
  • Add the correct amount of clarifier into your swimming pool. Be sure to follow the packet instructions as how much you use can vary depending on the type you purchase, the size of your pool and even contributary factors like the weather/ season.
  • Run your filter system overnight, ensuring that nobody uses the pool in a 24 hour period. This should allow the clarifier to clump the particles together and allow the filter system to remove most of them.
  • Vacuum out any clumped particles on the bottom of the pool that the filter did not remove. Keep the filter running as you vacuum, this will help break any further pieces down further and eliinate them. .
  • Test your swimming pool water for both your sanitizer and your pH levels. When the pool levels are back to normal, the pool is safe for swimming.

You should now have the answer to the question – why is my pool cloudy?

Here’s to swimming in beautiful clear water and a happy healthy pool!