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.
Calcium hardness (CH) The calcium hardness is a measure of the amount of lime dissolved in the water. Water with a CH of less than. 100 ppm (mg/l) is described as soft water and draws lime out of, for example, the concrete of cast pools and tile. grouting, leading to disintegration.