Pool Salt Blasting is a gentle alternative to glass beads and safely removes calcium, mineral deposits, oily residue, mold, algae and scale from pool waterline surfaces. Mineral Salts also called “Kieserite”, is a unique mineral imported from Germany. Our supplier turns the raw material into an Engineered product by screening it to ensure uniform particle size distribution and adding anti-clumping technology to ensure constant flow occurs while blasting. Kieserite is a 3.5 Mohs hardness which is softer than pool tile but hard enough to remove pool calcium.