Cal Silencer is a flocculent blend that is typically used to shift deposits of silt, mud and sand from open drains. Cal Silencer gives the silt particles a buoyancy in water and by putting a small electrical charge on each particle it causes them to repel each other. Material treated with Cal Silencer is unlikely to form a sold mass again. This enables the silt and the sludge content of heating systems to be removed quickly and effectively.