Home » Pool Clarifier: How to Clear Up Cloudy Pool Water

Pool Clarifier: How to Clear Up Cloudy Pool Water

So you’ve heard that pool water clarifier could clear your cloudy pool water. Good news! Clarifier will clear mild to moderate cloudiness in your pool with minimal effort so you can have your water sparkly and clear in no time.

Clarifier: how to fix cloudy swimming pool water

How to Clear Up a Cloudy Pool Water Using Clarifier – Summary

For those wanting a quick fix, here’s a summary of how to clear a cloudy pool using liquid clarifier or clarifier tablets. This will help chlorine or cloudy salt pools.

And detailed instructions can be found further in this article.

  1. Check your pool water is balanced especially the pH.
  2. Add pool clarifier – follow the directions on the packet.
  3. Filter your water continuously for 24-48 hrs. Then filter for at least 3 more days, 10 hours a day or until the pool water is clear.
  4. Clean or backwash the filter.
  5. Rebalance the pool water.

Recommended Pool Water Clarifier

You can pick up pool clarify here.

Super Blue Pool Clarifier
  • Quickly clears cloudy water and prevents future haziness
  • Use with all filter types - will not clog filters
  • Doesn't affect pH or other chemicals

What’s the difference between tablets and liquid?

Both the liquid and tablets work in pretty much the same way. With the liquid clarifier, you’ll need to measure out the amount needed since it’s in liquid form.

Clarifier tablets are easier in a way since you do not need to measure anything. Just drop in the required number of tablets.

An added feature is some clarifier tablets are slow-release – which means they’ll keep clarifying and continuously treat your water.

What is Pool Clarifier & How Does it Work?

Your pool water has lots of microscopic bits (yes that’s the technical term) or particles suspended in it. When there’s a large amount of these particles in the water, it will look cloudy.

The problem is, these tiny particles are smaller than what your filter can collect. So they get left in suspension in the water. When there is enough of them in the water your pool water will look cloudy.

This is where pool clarifier comes in. Pool clarifier is simply a coagulant. A coagulant clumps together these smaller particles into larger particles called “flocs”. These larger particles are then able to be removed by your filter leaving you with clear pool water.

As a side note, humans have been using clarifiers as early as ancient Egyptian and Roman times. They are still used in pretty much every water treatment process today.

Pool Water Clarifier Ingredients

Liquid clarifiers contain water along with an active ingredient like Aluminium Chlorohydrate (Cationic polyelectrolyte). Clarifier tablets use a similar chemical except. Since they’re a dry tablet, they don’t contain water. Tablets are often more concentrated than the liquid form.

Different Types of Swimming Pool Clarifier
PolyDADMAC – this is a very common type of pool clarifier and contains ammonium chloride. Just in case you want to show off your chemistry knowledge, the full name for PolyDADMAC is Poly Dimethyl Diallyl Ammonium Chloride.

Aluminium Sulfate – this is also a very commonly used ingredient in pool clarifiers. Aluminium derivatives are commonly used in water treatment plants around the world to help clear water.

Polyacrylamines (PAM) – they often come in gel or tablet form. They are again used in water treatment plants and in other processes like paper making.

Natural Clarifiers – it is possible to buy pool clarifiers made from natural ingredients. Natural clarifiers can be made from Chitosan. Chitosan is something that is made from crustaceans.

So Which One Do You Need?
You could use any of these. They are all common in water treatment and have been used safely for many years.

We recommend this one here.

What’s the Difference Between Clarifier and Flocculant? Which One Do I Need?

Both clarifier and flocculant will clear up a cloudy pool. However, there are a few key differences between clarifier and flocculant (or floc).

Clarifier Vs Flocculant

As explained earlier, clarifier works by clumping together small particles into bigger particles which then allows your filter to capture them thus removing them from the pool water.

Pool flocculant, on the other hand, works similarly by joining together particles but instead of the particles staying suspended in the water, they drop to the bottom of the pool floor ready to be vacuumed up.

Which One is Better?

Clarifier is great for mild to moderate cloudiness but won’t work when the water is extremely cloudy or swamp-like. It’s also great for ongoing maintenance and to keep your water looking sparkly and clean.

Clarifier is a lot slower to work than flocculant and usually takes several days to clear up a pool. You’ll need to continuously filter your pool for 24-48 hours after using clarifier and then filter 8-10 hrs per day for several days – but that’s about the only work you’ll need to do.

If you’re in a hurry or have extra cloudy pool water, flocculant is what you want. It works in as little as a few hours. However, there is a price to pay for that speed. Cue the evil laugh – hohoho!

Since flocculant drops everything to the pool floor, you’ll need to manually vacuum up the mess. And you’ll need to set your filter valve to “waste”. You don’t want to run all that muck at the bottom of your pool through your filter. If you do, you will block up your filter.

So not only will you spend quite a bit of time vacuuming, but you’ll also lose a lot of water since the water that is sucked up in the vacuuming process will be sent to waste instead of being circulated back into the pool. But you’ll have clear water in a few hours.

Another important point about floc is that you normally can’t use it with cartridge filters – unless you have special plumbing with a waste valve installed. If you don’t have a waste valve, you’ll block up the filter and will be up for a new filter before you know it.

Clarifier Vs Flocculant Pros & Cons

Pool Water ClarifierPool Water Flocculant
Time to Work2-5 days2-4 hours
Work RequiredRun filter for 24-48 hours, re-balance waterManual vacuum of pool, re-balance water
CostComparable to Flocculant Comparable to Clarifier
Water WasteNoneYou’ll lose a lot of water when vacuuming – need to top up
Fixes Cloudy WaterYes – mild to moderate cloudiness Yes – fixes very cloudy water
When Can I Swim?20 mins after usingA few hours – wait until floc has dropped to bottom

You can read more in our article on pool flocculant.

How to Use Pool Clarifier

Using Clarifier in your pool is easy. It’s important to note that although clarifier may clear your water, if you haven’t solved the underlying issue, the water will cloud again.

Reasons for cloudy water include algae, incorrect pH levels (in particular, if the water is too alkaline), the filter needs cleaning/backwashing/replacing.

Related: How to Backwash a Pool Sand Filter & How Often

Another reason is not enough chlorine/sanitizer and finally, check that you’re running your filter long enough and it’s working properly. In swimming season you’ll need to run it more. It’s also good to run it longer after heavy rain and wind as there will be more contaminants in the water that need to be filtered out.

To use clarifier, make sure the pool has been balanced correctly, run the filter for at least 24 hours. Then you simply follow the directions on the pack and filter, filter, filter your water. It will take 2-5 days to work. You may also need to vacuum the floor of the pool after a day or so.

Pool Vacuum - how to fix cloudy swimming pool water with clarifier

For liquid clarifier, dilute it in a bucket first, then pour it in the water – it’s best to walk around the pool whilst doing this to disperse it. For clarifier tablets, just drop the required number in the skimmer box.

Do not use too much clarifier. Too much clarifier may have the opposite effect and cloud the water further. Read on to see what happens if you put too much clarifer in.

A note on old vs new filters – pool filters tend to work better when they are a little older. This is because, after some use, the filter traps microscopic particles in the filter medium partially blocking it up. This means that the filter is now able to trap even smaller particles that would ordinarily pass through a new filter.

How Much Clarifier to Put in Pool?

The amount of clarifier to put in a pool will vary depending on the manufacturer. You’ll need to calculate the volume of water in your pool first. Then it’s simply a case of following the directions on the pack.

Clearing Cloudy Water with Pool Clarifier – Long Answer

There are several things you should investigate before using clarifier to clear up cloudy pool water. You want to fix the underlying issue before turning to clarifier.

Cloudy water is usually caused by a chemical imbalance, environmental causes such as heavy rain, dust or pollen in the air, swimming in the pool, algae or not enough filtering and cleaning.

If you don’t think any of these things are the cause of cloudy water or you need a quick-ish fix, go ahead and use clarifier.

  1. Check Your Pool Water is Balanced
    Test your pool water with test strips, a chemical test kit or take a sample to your local pool store for analysis. Your pool water should be balanced as follows:

    pH: 7.4 to 7.6
    Chlorine: 3ppm
    Cyanuric acid (stabilizer): 100ppm
    Alkalinity: Around 125ppm plus or minus 25ppm
    Calcium Hardness: 150ppm to 400ppm
  2. Add Pool Clarifier – follow the directions on the packet.
    It’s super important that you carefully follow the directions on the package. You will likely end up with cloudier water if you add too much clarifier. You’ve been warned!

    To add the correct amount you’ll need to know your pool water volume.

    Here’s how to calculate the pool water volume.
    1. Measure the pool dimensions in feet.
    2. Calculate the average depth in feet (measure the depth of the shallow end and then the deep end, add them together and divide by two).
    3. Multiply these numbers together, then multiply by 7.5 to get the volume in gallons.

    Now measure out the correct amount according to your pool water volume.

    For liquid clarifier, dilute the required amount in a bucket of water then pour it in the water walking around the pool at the same time to distribute it.

    Clarifier tablets can be added to the skimmer box or in the pool.
  3. Filter your water continuously for 24-48 hrs then for several more days for at least 8-10 hours per day.
    You’ll need to filter, filter and filter again. This will disperse the clarifier firstly and then when it starts to coagulate and work, it will allow your filter to start picking up the microparticles that cause cloudiness in water.

    It may take 3-5 days of filtering to clear water up.
  4. Re-balance the pool water.
    When the water is clear, you can re-balance your water.
  5. Enjoy swimming again in crystal clear water!

    Note: if things haven’t gone to plan and the water still isn’t clear, you can re-dose but wait for several (at least 5 days) before doing it again so you don’t risk adding too much clarifier.

Pool Water Clarifier FAQs

What if I Put Too Much Clarifier In?

Clarifier is something you really need to be careful about adding the correct amount to your water.

Adding too much clarifier can have the opposite effect where it acts as a dispersant instead of a coagulant. If you accidentally add too much clarifier, what you do depends on the clarifier and how much you overdosed by.

First of all, don’t panic. Here’s what you can do:

  • Skim the surface of the pool if you notice a build up on it
  • Shock your pool to break up polymer based clarifiers
  • Filter, filter, filter – over time you will filter it out

Is it Safe to Swim After Using Pool Clarifier?

Girls Swimming In The Pool -  clarifier: how to fix cloudy pool water

Yes, it’s normally safe to swim almost immediately (about 20 mins). But check the directions on the pack first.

Swimming in your pool after adding clarifier is good for the circulation of the pool water and helps to stir up the particles on the floor of the pool so they can then be sucked in by the pool’s filter.

Just know if you’re planning on having people over and you want clear pool water, clarifier will take several days to work. Use a flocculant if you’re in a hurry.

Can I Use Pool Shock at the Same Time as a clarifier?

It’s not a good idea to use pool shock at the same time as clarifier. Some clarifiers are polymer based and the shock can act to break up the polymer causing the clarifier to be ineffective.

It’s best to shock your pool before and wait a day or two before adding clarifier.

Related: How To Shock A Swimming Pool For Beginners (In 8 Easy Steps)

How Long Does Pool Water Clarifier take to Work?

Clarifier does take some time to work, unlike flocculent. It usually takes 3-5 days. From the time you put the clarifier in the water, you’ll need to filter your water for at least the first 24-48 hours, then as much as possible.

Note that if you have algae, you should take care of that before using clarifier. Clarifier won’t work if that’s what’s causing the problem.

If you’re getting cloudy water regularly, there may be other reasons. This could be environmental. Such as heavy rain, lots of dust or pollen in the air. It could be because your pool is out of balance or it may mean your filter isn’t working properly.


If you have mildly to moderately cloudy water, using a clarifier is a great way to help clear that water. You’ll need to be patient and wait a few days for it to clear your pool.

If the water clouds again quickly – within a few weeks – remember to check for other underlying issues. You don’t want to just treat the symptoms rather than the cause.

Recommended Products


Pool Test Strips or Liquid Testing Kit

Pool Shock


Man and Baby in the pool - Clarifier: how to fix cloudy swimming pool water

3 thoughts on “Pool Clarifier: How to Clear Up Cloudy Pool Water”

  1. Hi! We have a metal frame pool, holds 3500 gallon. We use a salt water system. We recently had to replace the pool pump itself. Now our pool is a cloudy green color. I ve shocked it, added a clarifier, baking solda, algicide you name it s been put in the pool. Today I checked the levels and the chlorine level is at a 10, clearly can t swim in this. I turned off the salt water pump and left the regular pump running. How can I get rid of the cloudy green color, I want my pretty clear blue pool back ???? overly frustrated!


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