Several chemicals should be added to a swimming pool on a regular basis to keep the water safe and clean. Many swimming pool owners become unhappy with the common chlorine based chemical routine, and look to alternative sanitizers (such as Baquacil or SoftSwim) called biguanide based pool chemicals. Unfortunately these alternatives prove to be more expensive initially to purchase the chemicals, and cause problems over time which temporarily close the pool down.

If used in large quantities, or if not maintained properly, chlorine may irritate the eyes and skin of swimmers. Biguanide based swimming pool chemicals are much softer and have almost no affect on swimmers, but these chemicals are not capable of controlling organic contamination. Examples of organic contamination might be wastes left behind by swimmers or material that has blown or fallen into an outdoor pool, which promotes the growth of algae. While a chlorine swimming pool instantly neutralizes harmful organics, a biguanide swimming pool requires the addition of concentrated hydrogen peroxide on a regular basis. This liquid hydrogen peroxide solution proves to be more dangerous than chlorine to both store and handle.

Because biguanide based sanitizers cannot control organic contamination, microorganisms present in the pool water will build a resistance to the biguanide chemical over time. Like an evolving virus, these organisms become used to the biguanide sanitizer and form a type of water mold or slime. This ugly slime can only be eliminated with a strong dose of chlorine-based pool shock. The chlorine pool shock quickly removes the water mold, but also destroys all of the biguanide in the water. The immediate result of the chlorine and biguanide chemical interaction is very cloudy water which turns several unnatural colors, making the swimming pool unsafe to use for several days or weeks. Rather than risk further organic contamination and lost swimming time, most pool owners return to a chlorine pool chemical routine.

Chlorine is the right pool sanitizing chemical in every situation, except when a swimmer has developed allergies to the chemical. Pool chlorine is relatively inexpensive and easy to use, when used properly. With a basic understanding of pool water chemistry, and an easy weekly pool maintenance routine, any home owner can maintain a backyard pool with very few problems.