GLB Stain Magnet 2.5lb.

This granular formula quickly eliminates metallic stains from pool surfaces with no need to test the water or close the pool. – Use weekly to eliminate stains, prior to using GLB Sequa-Sol Sequestering Agent. – Compatible with most pool surfaces including gunite, most plaster, concrete, vinyl and fiberglass. – NOT intended for use on pools with black plaster. – Compatible with chlorine, bromine, ozone, biguanide and salt water chlorine sanitizing systems.