Water Clarifiers work by bringing tiny particles together, making a larger mass, that a filter can pick up easier.
Clarifiers can bring a hazy pool clear and make a dull pool sparkle.
They are an excellent weekly addition to swimming pools and hot tubs, however always follow the manufacturers recommendations. Overdoing it with a clarifier could actually give you the opposite results.
We've included Flocculants in this category as well, even though they are technically different, it's easiest to think of Flocculants as a strong clarifier, that keeps working until everything is so heavy it falls to the bottom of the swimming pool. Many Flocculants can be used as a "Filter Aid", which causes the product to work more like a Clarifier.