Southern Association of Colleges and Schools Commission on Colleges. Bob Jones University is a candidate for accreditation with the Southern Association of Colleges and Schools Commission on Colleges to award associate, baccalaureate, masters, and doctorate degrees.
hthÂ® calcium hardness increaser, 4 lbs. hthÂ® calcium hardness increaser, 4 lbs., is used to raise the calcium hardness of swimming pool water. Low calcium hardness may cause the pool water to be corrosive, resulting in damage to pool surfaces and equipment.
Permanent hardness is hardness (mineral content) that cannot be removed by boiling. When this is the case, it is usually caused by the presence of calcium sulfate and/or magnesium sulfates in the water, which do not precipitate out as the temperature increases.