Pool Professional flocculant
The Pool Professional flocculant combines the smallest, non-filterable suspended particles in the water to form a larger floc. The sand filter system then simply filters the floc out of the swimming pool water. Use a flocculant only with sand filter systems; it is not suitable for cartridge filter systems. Note that flocculation in the pool only works ideally, if the pool water also has the appropriate pH value in the range of 7.0 to 7.4.