Mr Pool Man's In-Depth Resource for All Things Pool

How To Fix Cloudy Pool Water



When you have a cloudy pool, it can be a very difficult and time-consuming process to get it clear. Sometimes, your swimming pool will turn cloudy overnight!

I’ll explain the reasons your pool got cloudy in the first place, then share a few methods on how to fix the cloudy water. It won’t be a difficult and time-consuming process if you follow these methods.

Before we talk about how to fix you cloudy pool water, let’s first understand what causes it.

Why Do I Have Cloudy Pool Water?

There are so many causes of cloudy pool water, but I have broken it down into three main causes.



1. The Pool Filter

Your filter system constantly cleans the water in your pool. Without it, you’re left with stagnant water that could become cloudy. Pool clarity is 9 times out of 10 linked to your filtration. If you are experiencing a cloudy pool, something's up with either your sand or cartridge filter.


2. The Environment

Everything around your pool can cause your water to be cloudy, that includes: weather, birds, construction, trees, gardens, the sun, people, and pool algae.


3. Pool Chemicals

An excessive amount of pool chemicals can cause your water to be cloudy. That includes: high pH, high alkalinity, high chlorine or other sanitizers, and high calcium hardness. Usually, running your filter like usual should help even these out over time, though if you do have an inbalance we'd recommend testing your water and contacting us for help on how to fix it. 










How To Clear A Cloudy Pool

Once you have fixed all the possible problems that can cause your water to be cloudy, now we can work on a cloudy pool water fix. Here are 3 ways to clear your cloudy swimming pool:


1. Get your filtration in check

Use the below steps for either cartridge filter or sand filter to ensure your filtration system in running correctly. Good filtration = water clarity.

If you have a Cartridge Filter:

1. When was the last time you cleaned your cartridge? If it was a while ago (weeks or months depending on how much use your pool is getting) take your cartridge out and give it a good hose down.
Tip: If you are after a thorough clean, soak your cartridge in a tub of clean water with a cup of Nappy San overnight (the same stuff that you use in the laundry in the pink tub). Nappy San contains the same cleaning chemicals as your expensive cartridge filter cleaning chemicals. Follow this by a good rinse with your garden hose the next day.


2. Have you recently added any flocculants or clarifiers to your pool? As your cartridge filter is made out of layers of paper, these two chemicals will clog your cartridge to the point of no return and should be avoided at all costs if you use a cartridcge filter as your filtration system. You can use them if it's an emergency, though be prepared to be replacing your cartridge filter element(s) when you're done.


3. How old are your cartridge filter element(s)? Depending on what chemicals pass through them, pool usage, how often they are cleaned/maintained etc, cartridge filters have an average life span of anywhere between 1-5 years. If your cartridges have seen better days, it could be time to replace them. Mr Pool Man can help you with this with our large range of cartridge filter elements. Can't find the one you need? Contact us with a photo of your system and/or your dimensions of your original cartridge filter element (length, width and hole width) and we'll be able to find it for you. 


If you have a Sand Filter:

1. When was the last time you backwashed your sand filter? If it's been a few weeks or months between backwashes (depending on the usage of the pool) you could be due for a good backwash. Rule of thumb is to backwash once a fortnight. Chances are you'll notice that the water that comes out during the backwash is very brown and dirty, this means that you should be doing it a bit more often! Let that backwash run for 2 minutes or until the backwash water turns clear.  Set the handle back to filter and you're good to go.
Not sure how to backwash your sand filter? Here's a simple step by step:


1. Turn off the pool pump.

2. Set the filter valve handle to the BACKWASH position and ensure the handle locks in place.

3. Turn on the pump and backwash for 2 minutes or until the water in the sight glass (located on the filter) is running clear.

4. Turn off the pump.

5. Set the filter valve handle to the RINSE position and ensure the handle locks in place.

6. Turn on the pump and run the rinse process for 1 minute or until the water in the sight glass is clear.

7. Turn off the pump.

8. Reset the Filter Valve to Filter and ensure the handle locks into place.

9. Turn on the pump.


2. When was the last time you changed your sand/media in your filter?
Filter sand lasts for anywhere between 8-10 years. If you're backwashing your filter and you're still noticing dirty water coming out of the backwash after 2-3 minutes or no clarity in your water following the backwash, this could mean sand change time. Mr Pool Man offer sand change services on the Central Coast of NSW in Australia (expanding soon), or you can go DIY with a slurpee to slurp the sand out, and picking up bags of sand from your local pool store. We are more than happy to provide any sand change advice to you over the phone or via email, contact us here.


2. Use A Pool Clarifier

Pool water clarifier's are a good quick fix, though should not be used if you are sporting a cartridge filter (it will clog the paper pleats to the point of no return, leading to replacing your cartridge filter element).

Pool clarifiers work to gather the tiny particles that are making your pool water cloudy and bring them together to create bigger particles so that your filter will have a better chance of picking it up. This is called a coagulant which is a term used when describing blood clots.

The particles alone will have a hard time being picked up by your pool filter, so this chemical “clots” them together and your filter now will be able to trap them. 

Most swimming pool chemical retailers will carry more than one form of swimming pool clarifier. Just ask if the chemical is a coagulant and you will be well on your way to a crystal clear swimming pool.




2. Use Pool Floc (Flocculant)

A chemical called Floc or Flocculant is a great idea if you’re in a rush, or would like to see your swimming pool cleared up quickly. Again, a flucculant should be avoided if you are sporting a cartridge filter, as it will clog the paper pleats. You can use it in an emergency, but be prepared to replace your cartridge filter element in the weeks to come. 

Lets say you have a pool party tomorrow and your swimming pool is cloudy. By using Pool Floc, you can clear your cloudy swimming pool overnight (with a little extra work on your part). Floccing your swimming pool is a great method, but it’s very time-consuming and difficult.

Pool Flocculants work by gathering all the particles, that are making your water cloudy, and sending them to the bottom of your pool, creating a huge cloud on the floor of your pool. Unlike a water clarifier, this chemical WILL NOT help your filter to pick up the particles, because all of the cloudy pool particles are now at the bottom.




At this point, you will need to manually vacuum up that cloud using your pool pump, not an automatic pool cleaner. When vacuuming, you want your filter setting to be on the “waste” or “backwash” option if you are using a sand filter.





The idea here is to vacuum up the cloudy water right OUT of your pool, because putting that much dirty water through your filter WILL NOT work and will send that dirty water right back into your pool.

By vacuuming out to “waste,” it will never run through your filter system. You are going to lose a lot of water in your pool, so make sure to keep a fresh hose of running water in your pool during vacuuming.

Also, you must use a manual vacuum for the process. Automatic pool cleaners will not work and will just end up blowing the cloudy you created at the bottom of your pool, right back up. Again, it is difficult and a lot of water is wasted, but it will clear your pool in 24 hours if done properly.



3. Use Your Filter System and Bottom Drain(s)

Your pool’s main skimmer is located at the top of your pool and helps to clear the top, which does not help to collect the cloudy particles that are at the bottom of the pool. Knowing this, we need to help the filter get to those particles.

You can achieve this two ways:

  1. Constantly stir up the water, by swimming or with a pool brush, so that it pushes the particles closer to the top of the pool.
  2. Turn on the bottom drains.

Every inground pool should be equipped with 1 or 2 bottom drains, so it’s easy for you to utilize them. This will allow the filter to start pulling water off the bottom of the pool, where the cloudy particles are, and circulate the clean water back to the top.

This works great, but what if you have an above ground pool that doesn’t have bottom drains? We have come up with a little trick to mimic the effect of a bottom drain in an above ground pool.

Simply hook up your manual vacuum cleaner, as if you were about to vacuum your pool, but instead, leave the vacuum at the bottom (in the middle of your pool) and turn it upside down. Now your pool filter will be pulling water from the bottom of your swimming pool using your manual vacuum and releasing the clean filtered water up top.

These are three different methods of how to clear a cloudy pool by using swimming pool chemicals and your pool’s equipment. If you have any questions about your cloudy pool, be sure to contact us.


What method would we recommend?

Number 1 is the clear winner in our eyes. Having a good quality filtration system and staying on top of cleaning that system regularly (fortnightly) will provide you with clarity in your water.


Happy Swimming!



Comments (1)

Another effective product

19 October 2015
Cloudy Pool Cure another effective product to remove cloudy water. One pod efficiently works in 15,000-gallon pool if you have bigger use both pods. See the product here <a href="">Cloudy Pool Cure</a>

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