It may seem intimidating, but the job of keeping your water clean is a fairly simple & straightforward task. You simply have to make the water poisonous to the bacteria, algae, mold and other unwanted guests that want to live in your water and make it green. The single most important factor in doing this is maintaining a minimum level of sanitizing chemical. However, for this chemical to be effective, a few other chemicals and properties of your water must be monitored and maintained.
While there are other chemicals on the market for pool water, the least expensive, most effective, and most readily available is chlorine.