Pool owners often get confused about the terminology or different names that chlorine is referred to by. Simply speaking, the two primary types of chlorine that we use to treat our pool water are granular which is a dry or powder form, and liquid chlorine that comes in a jug. Of course there are chlorine tabs which is really just dry chlorine pressed and compacted into pool tablets or sometimes referred to as pool pills. Where the confusion often comes in is when retail pool stores call granular chlorine “shock”, “super shock”, “sock it”, and various other marketing terms.  What pool stores and pool supply retailers don’t usually tell you is that most of these chlorine products are simply ordinary 65% strength granular or dry chlorine. Pool supply stores package the granular chlorine in handy 2-3 lb plastic bags and charge a much higher price than if you were to buy a 25-50 lb bucket of granular chlorine.  By calling the chlorine packets “shock” or some other name designed to make you think it is a special form of chlorine used just for super chlorinating or shocking your pool water, the price of these packets is actually just shocking your wallet!  While there are indeed higher strength granular or dry chlorine products sold in some pool supply stores, the majority of granular “super chlorinating” or “shocking”  products are simply standard strength dry chlorine available at a much cheaper price. Granular chlorine has a fairly long (6-12 months +) shelf life.  So do yourself AND your wallet a favor.  Buy a 25-50 lb container of granular chlorine to use for shocking or super chlorinating your pool water throughout the swim season.