Both types of hardness is permanent hardness and alkalinity. Both types of hardness is defined as total hardness. Hardness, carbonate and bicarbonate ions from the composition from being known as alkalinity or hardness. This is called temporary hardness because it can eliminate the water by boiling. On the other hand, permanent hardness, boiling water alone can not be resolved because it is the accumulation of sulfate, nitrate and other hard metals.