Pool water clarifier in action

Pool Water Clarifier: How To Fix Your Cloudy Pool

There’s a party in your pool and you’re not invited! Tiny particles have taken over and they’re beginning to appear as cloudy water. This shindig won’t clear up on its own though. A product called pool water clarifier can help, but it’s not the only solution to fixing cloudy water. If your pool gets cloudy regularly, it’s likely the problem is originating elsewhere and you need to look a bit harder!

So if your head is as cloudy as your pool water, we have the solutions you need to get your pool back to being crystal clear.

In this guide to pool clarifier, we’ll cover:

Let’s clear those clouds!

What does a pool water clarifier do?

It’s quite simple really. Your pool filter will collect most of the particles in your pool. But the smallest of particles slip through the filter and continue to circulate around your pool. This happens for example with as skin and oils from our bodies. 

The more particles that slip through the cracks, the cloudier your pool water will become. So the use of a pool clarifier will temporarily eliminate this problem. Pool clarifier binds (coagulates) tiny particles together, making them large enough for your filter to pick them up. 

Here’s how.

What’s in a pool water clarifier?

Clarifiers can contain different chemicals, but they all have one goal: to create a polymer, which is a chain of molecules made up of many single molecules (monomers).

This molecules will chemically link together (coagulate) when the positively charged ions in pool clarifier collide with the negatively charged cell structure of organic material that makes your pool cloudy.

Clarifiers are just science doing it’s thing. There are various polymerising pool water clarifier ingredients that are derived from a variety of places:

  • Aluminium chlorohydrate (cationic polyelectrolyte): made by combining aluminum hydroxide and hydrochloric acid, it is also added to deodorants and antiperspirants.
  • Ammonium chloride (PolyDADMAC): made by combining ammonia with hydrogen chloride or hydrochloric acid, it’s also an additive in bread and liquorice.
  • Aluminum sulfate: made from cryolite, clays, or by adding aluminium hydroxide to sulfuric acid. It’s also added to deodorants, to food as a firming agent, and to animal food as a bactericide.
  • Chitosan: made from crushed crustaceans and marketed as a natural pool clarifier alternative.

Safety tips

  1. These chemicals are not safe enough to eat, so don’t go storing your water clarifier in the food pantry.
  2. Always keep anything you add to your pool in a secure area, away from small hands, paws, and claws.
  3. Clarifiers should only be out and about when you’re using them in your pool, with caution.

Which pool water clarifier should I use?

You may have noticed a few different types of clarifiers, but they can all be split into two coagulator categories. 

  • clarifiers: coagulated particles can be collected by your filter.
  • flocculants: coagulated particles sink to the bottom of your pool to be vacuumed.

Pool water clarifiers and flocculants are sometimes referred to as “water clarifiers”. Chemically, pool clarifiers and flocculants do the same thing, but the results are different.

If you’re not sure whether to choose a pool clarifier or flocculant, let us explain the differences for you here. Some of the best pool clarifiers are:

The type of water clarifier you can use also depends on what filtration system you have set up.  Pool water clarifiers are good for all filters, whereas flocculant is good for sand filters and diatomaceous earth (DE) filters.

When else you should use a pool water clarifier

A pool clarifier can be used as a preventative measure, stopping particles from building up and appearing as cloudy pool water. But if you find you need it regularly, there might be other things going on.

Typically, water clarifiers may need to be used at the beginning of your pool’s life, with a few more recommended situations below.

1. After clearing algae

Why: A water clarifier won’t clear algae blooms in your pool.

When: Use a water clarifier after you’ve killed an algae bloom as it’ll help to coagulate dead algae particles in your pool water.

If you’ve got green in your pool, you’ll need to attend to that issue with chlorine and an algaecide before anything else, and fast.

2. After shocking your pool

Why: If you use a water clarifier with chlorinated pool shock, the polymers can be destroyed by chlorine before they ever get to coagulation. 

When: Add a water clarifier to your pool at least a day after the shock treatment has finished.

You could use a combination of the two with Clean and Swim’s non-chlorinated shock treatment and pool water clarifier. 

How to fix your cloudy pool water

Do you dream of a pool gleaming with sparkles which you can proudly show off to guests, but the clouds have got you down?

In just a few steps you can turn that dream into a reality, and before you know it, you’ll be reunited with your pristine pool once again. When you’ve got cloudy water, follow these five easy steps to fix it.

1. Check your pool equipment

First things first, give your filter a once over to make sure it’s still going strong. Pool filters need to be replaced occasionally and are vulnerable to wear and tear.

Cloudy water can be caused by a compromised filter, whether it be damage, leaks, or an unclean part of your filtration system. For the most part a happy filter makes for a happy pool (and happy you!)

Your pool pump, bottom drains, skimmer, seals, and piping fall into this category too. Investigate any possible mechanical or superficial damage that could be stopping your pool from filtering properly.

2. Clean your pool

After you’ve checked your equipment and before you add a pool clarifier to your pool, give your pool a good clean. As detailed in our guide to pool maintenance, this entails:

  • Skimming: to collect and remove any floating debris.
  • Brushing: to loosen up any deposits that may have settled on your pool walls.
  • Vacuuming: to remove debris from the pool floor (and ultimately pool).

Then don’t forget to:

  • Clear your debris basket: in your pool pump.
  • Clean your filter: with a hose down or chemical soak for cartridge filters or a backwash for media (sand) filters.

The cloudiness may come back soon after it clears if it’s due to debris or grubby equipment.

3. Shock and balance

Light pool cloudiness can sometimes also be cleared by simply shocking your pool. Give it a go before using a pool clarifier or flocculant and you could be pleasantly surprised.

Just remember to shock your pool in the evening and keep the pool filter running during the shock treatment overnight. After shocking your pool, balance the water chemistry (which is also a cause for cloudy water), top up the sanitiser levels, then observe.

If you want to know more about balancing pool chemistry, check our pool cleaning chemicals guide to find out more.

4. Use a pool water clarifier

If all else fails and your pool still looks like a giant paracetamol has been dissolved in it, you’ll want a pool water clarifier. If you’re in a quick fix on the morning of your pool party, consider using a flocculant instead.

How to use pool clarifier:

  1. Clear algae: if you have an algae bloom, tend to that first.
  2. Balance the pH levels: to 7.4 – 7.6 as the clarifier will only work in neutral water.
  3. Measure the volume of your pool: if you don’t know this, you can calculate it here
  4. Take note of the clarifier dosage: as advised by the manufacturer.
  5. Add clarifier to your pool: the method suggested by the manufacturer.
  6. Turn your pool pump on: so that the coagulated particles can run through your filter. The longer the pump runs, the faster the pool will clear!
  7. Wait: 2-3 days or until your pool turns sparkly clean.
  8. Clean your pool filter.
  9. Test and balance: pH, alkalinity, and sanitiser levels as pool clarifiers can change water chemistry.
  10. Take a dip!

5. Keep the water flowing

Lastly, and most importantly, make sure you’re running your pool filter for 8-12 hours every day.

Your filtration system needs to run for enough time for all of the water in your pool to pass through your filter at least twice per day. If the water in your pool isn’t circulating, there won’t be much filtering going on, and things can get dirty or cloudy pretty quickly.

And remember, a swim a day keeps the clouds away! Or so they say…

Pool water clarifier most frequent questions

Still scratching your head? Here you’ll find a few commonly asked queries about it.

How long does a pool clarifier take to work?

You’ll need to be patient when using a pool water clarifier as it can take two to three days to coagulate cloudy water and for your filter to collect the particles.

But time is on your side when using a flocculant as it can take as little as four to six hours to coagulate those pesky particles – although you’ll need to vacuum the pool!

The time it takes for any water clarifier to work will also depend on how many tiny particles have infiltrated your pool.

Can you use too much pool clarifier?

Yes, it is possible to use too much clarifier in your pool. Too much clarifier in your pool can cause an adverse reaction where your pool ends up remaining cloudy.

If this happens, it’s best to partially drain your pool and top it up with fresh water. You can then filter out the remaining pool clarifier overload, but be careful, too much clarifier will clog your filter. If you’ve accidentally used enough clarifier to clear all of the pools in your neighbourhood, you’ll need to fully drain your pool. 

It’s better to avoid adding too much clarifier in the first place by following the manufacturer’s recommended ratio of water clarifier to pool water.

Is there a pool clarifier substitute?

Using a household chemical like bleach is not a substitute for pool clarifier. The only alternative to using a pool clarifier is to maintain role-model maintenance behaviour:

  • Keep your pool water chemistry balanced constantly.
  • Keep up with proper pool cleanliness, again, constantly.
  • Circulate all of the water in your pool at least twice a day.

But keeping on top of all of this can be difficult to do.

So you might still need to use a clarifier on occasion (even if you’re scrupulous about water chemistry, cleanliness and circulation), as it’s inevitable that contaminants will enter your pool from swimmers.

Tip: To decrease the amount of these contaminants entering your pool, swimmers could do their bit by showering before they enter the pool.

This helps to reduce the amount of oils and dirt that wash off into your pool and cause cloudy water. But when the juices are flowing and the sun is shining, routines can easily be forgotten.

That’s when a pool water clarifier can save the day!

About the author
Adrian Hill
Adrian Hill

Hey! I'm Adrian, founder and pool expert here at Dolphin Pacific. I love spending time with family, fishing, and have been known to brew my own beer.

Signup To Our Newsletter!
Step by Step guide to pool cleaning Graphic square
Download The Guide

Learn how to keep your pool sparkling clean step-by-step!

How our ordering process works.

Once you have added the products to your cart, initiated checkout and completed the order, it is sent to our sales team. We will place the order with our stockists and you will be contacted when your order is ready to be picked up locally, or delivered to your door.

When do I pay for the products?

Payment is made to our stockists. If you choose to pick up your order from the stockist, payment will be required upon receiving the order. For deliveries, you will enter your card details through a secure form and the order will be sent to your door.