It’s something no pool owner wants to find – cloudy, murky pool water.
If you have noticed the water in your pool gradually looking duller and duller, it’s probably because of a chemical imbalance.
If your pool is outdoors, then there is potentially debris in the water too causing it to become cloudy.
The truth is, there are numerous reasons why your pool water has become cloudy such as lack of sunshine, heavy rainfall, and certain algae growth.
Thankfully, there are ways to treat this. Two main methods are by using a pool clarifier or flocculants.
Today, we will be discussing both methods to find out which one is best for you and your pool problem.
What is a Pool Clarifier?
You have probably come across a pool clarifier if you own a pool.
Essentially, this is a liquid containing polymers, which are molecules that bind as coagulants on microscopic particles that your filters can’t catch.
The addition of a clarifier enables these microscopic particles to cluster together, allowing your filter to eliminate them as part of its normal operation.
When used properly, this can successfully clean cloudy water in your swimming pool.
What is a Pool Flocculant?
Another method of clearing cloudy water in a pool (see also ‘How To Clear Green Pool Water In 5 Steps‘) is by using a pool flocculant.
Basically, this is a powdered material, also referred to as ‘pool floc.’ It encourages particles to thicken and cluster together in the same way as a clarifier does, but the particles are larger and, therefore, tend to sink to the bottom of your pool rather than passing through the pool’s filter.
Bear in mind, though, that flocculants tend to work best on D.E. Filters and sand.
When you need to check your water levels, you should adjust the flocculant as required.
Once you have adjusted the levels, you can leave the flocculant in the pool for around 8 to 12 hours.
However, you should always read the product’s labels and instructions as this can vary from one to another.
During this period, simply leave the pool alone and let the flocculant do its work.
You can then gently vacuum your pool with a manual vacuum.
Sometimes, however, you may notice the pool getting cloudy again. If so, leave the water once again and let the particles settle.
When your pool is finally clear, simply wash it and thoroughly rinse and filter it.
Pool Clarifier vs Pool Flocculants: Differences
As you can see, pool clarifiers and pool flocculants seem to be very similar. But, there are some distinct differences between the two.
Both clarifiers and flocculants are types of coagulant agents (thicken substances).
Both achieve the same results but through different means. The main difference is the time taken for the chemical reaction to take place and how much effort is needed to complete the task.
Clarifiers tend to come with the least amount of work needed to achieve clearer pool water.
These are superb for very fine silt as well as water with only a light cloudiness.
However, one downside of clarifiers is that they typically take several days to work properly.
Pool clarifiers are safe to use with DE, sand, and cartridge filter systems. For the best results, a clarifier needs the pool’s pump (see also ‘Can An Extension Cord Be Hooked Up To A Pool Pump That’s Above Ground?‘) and filter to run non-stop for at least 24 hours.

Compared to a pool flocculant, a clarifier is the mildest of the two chemicals. Therefore, it takes longer to work.
If you want a quick fix to your pool’s cloudy water, a clarifier may not be the best option.
That being said, a clarifier is ideal for light cloudiness and can be used as part of a regular cleaning routine to keep your pool water clear and clean.
A flocculant works quickly. In just a few hours, you can see results. And, not only this, but flocculants tend to be very effective.
However, there are a few downsides such as increased waste of water after use, the need for vacuuming afterward, and the fact that you can’t use flocculants with systems that have cartridge filters unless it has some sort of bypass.
Instead of needing a pool filter to clean the pool, a flocculent requires vacuuming.
Flocs work by gathering dirt into large clumps to stop them floating. Then, the dirt is dropped to the pool’s floor before being vacuumed.
If you need to clean your pool quickly before friends and family flock over, a flocculant is your better option.
You can use a floc for mild cloudiness as well as dark, murky waters. Nevertheless, because you have to vacuum, it’s not always the preferred method as you may lose some excess water in the process.
TIP: A flocculant should not come into any form of contact with your pool’s filter media.
If so, the dirt clumps could be catastrophic. Therefore, we recommend only using a floc with filters that have a bypass option such as DE or sand filters that sport slide or multiport valves.
Don’t use a flocculant with a cartridge system unless there is a bypass for the filter.
In Summary
As you can see, a pool clarifier and a flocculant both help to clear murky pool water.
But, if you want a quick fix, a flocculant is the better choice, but this comes with the added work of vacuuming.
If you have time to kill and want the easier option, we suggest using a pool clarifier.