How to Use Pool Flocculant

For every week’s maintenance Pool Clarifiers can work great but if your swimming pool takes a dive normally during hot summers with heavy usage, you are going to have to bring in the big guns and that’s when to use Pool Flocculants can save the day. How do you use Pool Flocculant?

  • Read directions
  • Turn filter to the ‘Recirculate’-for 2 hrs.
  • Adjust pH-7.4- 7..6.
  • Determine the amount using the volume of your pool to gals.
  • Dilute in a 5 gal. bucket-pour around pool edges
  • T/Off pump & leave sit for 8 hrs.
  • After 8 hrs., turn filter to ‘waste’, & vacuum pool
  • Refill pool-Balance chemistry.

The main ingredient in a pool (or spa) flocculants is aluminum sulfate. Clarifiers are often confused with Flocculents, which are similar but work differently for maintenance use Clarifiers of Pool Polishers for a dirty pool use a Flocculant.

How to Use Pool Flocculant


Both Flocculants and Clarifiers are considered coagulants, but the main difference is the time it takes for the products to work. A clarifier is a milder chemical that will take several days to completely clear up a cloudy pool, while a flocculant works almost immediately.

The first thing needed to do before adding flocculant to the swimming pool is to test your pool water. Quality pool flocculant comes in powder and liquid forms. Consult your pool supply store and let them recommend a good Flocculant Read the direction for how much you will need a  Pool Volume Calculator here’s a good one in any shape and size.

Knowing how many gallons of water are in your pool is important for determining things like the right amount of chemicals to add, heater size, and so many other decisions.

You are going to have to know the volume of your pool in gallons to figure out the amount to use. One cubic foot of water equals 7.48 US gallons; once you have calculated the volume of your pool in cubic feet, simply multiply it by 7.48 and the answer is the number of gallons of water your pool holds.

Square: Volume (US Gallons) = Side Length 2 × Average Depth × 7.48


What is Pool Flocculant?

A pool flocculant is a chemical that helps to remove small particles from pool water, these particles can include dirt, debris, algae, and bacteria. Flocculants work by clumping these particles together helping them settle out so that they can be removed from the pool H2O ……………………………………… Read more



 When should I use a pool flocculant?

If your pool falls out of control:

Cloudy pool water (milky color water)
Green color pool water
pH, Chlorine, Total Dissolve Solids, and Alkalinity (TA) tests become skewed

Clarifiers are used as preventive maintenance & filtering aid after shocking .………………………….. Read more

How to Apply Pool Flocculant


Applying Floc is easy but there are a few critical things you need to remember.

  1. Turn the filter to the ‘Recirculate’ setting.
  2. Make sure the pH level in your pool is balanced (between 7.4 and 7.6).
  3. Read the instructions on your package of flocculant. You’ll have to add the correct amount according to the volume of your pool.
  4. Once added, run the pool pump for two hours to properly circulate it and evenly distribute it.
  5. Read the directions on the bottle to find out how much water to add to the product to dilute it. Using a  five-gallon bucket is a great container to mix the chemical.
  6. Add the flocculant to the pool-Pour the diluted flocculant around the edges of the pool.
  7. Turn off the pump and leave the pool water to sit for 8 hours.
  8. After 8 hours, turn your filter setting to ‘waste’, because now it’s time to vacuum the pool and remove the dirty deposits (pool cobwebs) from the bottom.
  9. Check the pool water level. It will have gone down, because you’re vacuuming to ‘waste’, meaning you are removing water from the pool. Use a garden hose to refill your pool, and then re
  10. Balance your water chemistry.

Once the clumps form on the bottom of the pool, you’ll need to remove them by vacuuming the pool bottom. An automatic pool vacuum will not work. You’ll lose pool water using a pool flocculant. When you vacuum the clumps out, you’ll need to vacuum to the “waste” setting and bypass the filter.

Flocculents need to be vacuumed to waste and never to the filter. If you have already added flocculent to your pool and let it into your filter: for a sand filter, there is a great chance you will need to change your sand. Never use flocculant with a Cartridges Filter they good be damaged and could need to be replaced. 

Do not swim with flocculant chemicals in your pool. Wait until the floc has gathered all your pool’s impurities together always follow your flocculent manufacturer’s instructions on its label and vacuum them out of the pool before opening the pool to swimmers.

Pool flocculant can clear up your cloudy pool H2O in 1 to 2 days. Though it works faster than pool clarifiers, it will need 8 to 16 hours to clump together the particles before you can vacuum.


Why isn’t the pool flocculant working?

Reasons Flocculant didn’t Work:

You are using flocculant on living algae-you need to shock your pool with chlorine first to kill algae then settle
You didn’t wait long enough-Flocculant directions have a dozing rate & wait time.
Cloudiness in the pool could be caused by an in-balance ………………………………………………………… Read more


JimGalloway Author/Editor


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