What Chemicals Do You Need to Keep a Pool Clean?

There are several tasks required to keep a swimming pool clean. Weekly maintenance that includes removing floating debris, emptying the skimmer basket, brushing the pool walls and floor and vacuuming sets the stage for chemical additions. The dirtier you let your pool get, the more money you will need to spend for chemicals to clear the water. For example, if leaves are allowed to accumulate, they will decay and provide nutrients for algae to feed on, leading to more algae requiring additional chlorine and algaecide.

Water Balance

Before chemical additions, you must test the water to determine the base levels of three important water properties. The alkalinity, pH and calcium hardness usually require some adjustment to get them into ideal ranges. This will prepare the water for chlorine to sanitize it. Deviations from the ideal ranges lessen the effect of chlorine to the point where it becomes a negative factor, causing cloudiness in the water without sanitizing. Alkalinity needs to be between 80 parts per million (ppm) and 120 ppm. The ideal pH range is between 7.2 and 7.6, while the calcium hardness ideal range is 180 ppm to 250 ppm. The generic names of the products necessary to make these adjustments are alkalinity increaser, pH plus, pH minus and calcium hardness increaser.

Chlorine Pucks

Chlorine comes in two convenient sizes, either 1-inch tablets or 3-inch pucks. The pucks are less costly, and since there is less surface area exposed to the flowing water in the skimmer, they last longer than an equivalent amount of the smaller tablets. Chlorine kills bacteria, germs and small microorganisms, which if left unchecked could cause discoloration, cloudiness and an unhealthy swimming environment.

Chlorine Shock

Pool shock is a concentrated dose of powdered chlorine that, when released into the pool water, oxidizes and burns up any foreign material in the pool. The chlorine level spikes very high to around 9.0 ppm of chlorine during the process, so the pool should not be used until the chlorine level returns to normal, which is between 1.5 ppm and 3.0 ppm of chlorine. Adding pool shock is best in the late evening when the day's swimming is over. Since the sun acts like a chlorine magnet that pulls the chlorine out of the pool, the evening addition allows the chlorine maximum oxidation time over night. The next morning as the sun rises, the chlorine level will gradually decrease, usually until around noon. After a water test to verify the level, it may be back to normal and swimming can resume.

Algaecides

Chlorine is effective against algae, but can always use some additional help. Algaecides, when used in the correct maintenance dosages, provide an extra layer of protection from this slippery, slimy and unwanted pool guest. A stretch of hot weather may lower the ideal chlorine level in the pool, which begins to pave the way for the formation of algae. A concentrated algaecide, correctly dispersed at a rate of several ounces per 10,000 gallons, dilutes the product and poses no health threat to humans.

Metal Remover

If you fill your pool from a water source like a river or well or even an underground spring, the water source may contain some type of metal. Larger pool water testing kits contain elements to test for iron and copper. Separate kits for iron and copper are also available. Metal-removing products bind with metal molecules and neutralize their effect on chlorine. Untreated, the metals will cause water discoloration and make it very dark.

References

• Pool Chemicals to Add