Pool-Depot.com - your source for swimming pool parts, pool supplies, pool equipment and pool chemicals

Swimming Pool Terms Glossary

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

CAC Abbreviation for Combined Available Chlorine. Undesirable, foul-smelling, body-irritating compounds formed when insufficient levels of free available chlorine react with ammonia and other nitrogen-containing compounds (swimmer and bather waste, fertilizer, perspiration, urine, etc.). Combined chlorine is still a disinfectant but it is a much weaker, ineffective form of chlorine. Destroyed by Superchlorination or shocking.

Calcification The formation of calcium carbonate on the walls or pipes, or in a heater due to the precipitation of calcium carbonate.

Calcium One of the principal elements making up the earth’s crust. The presence of calcium in water is a factor contributing to the formation of scale and are a means of identifying hard water.

Calcium Carbonate Crystalline compounds formed in swimming pool and spa water when the calcium, pH and total alkalinity levels are too high. Once formed, the crystals adhere to the plumbing, equipment, pool walls and pool bottom. These crystals are better known as scale.

Calcium Chloride A soluble white salt used to raise the calcium or total hardness level in the pool or spa water.

Calcium Hardness The calcium content of the water. Calcium hardness is sometimes confused with the terms water hardness and total hardness. Too little calcium hardness and the water is corrosive. Too much calcium hardness and the water is scale forming. One of the basic water tests necessary to determine water balance. Minimum level 150 ppm. Ideal range 200-400 ppm.

Calcium Hypochlorite A compound of chlorine and calcium used as a disinfectant, sanitizer, bactericide, algaecide and oxidizer in swimming pool and spa water. It is available as a white granular material usually used for superchlorination or it is available as tablets used in a feeder for regular chlorination. It usually contains 65% available chlorine but is available as 70% and 75% also.

Calcium Ion An electrically charged particle of the element calcium in water. The superscript ++ or +2 indicates the valence or the number of electrons that calcium can donate.

Cal Hypo Common name for calcium hypochlorite

Cartridge A replaceable porous element made of paper or polyester used as the filter medium in cartridge filters.

Cartridge Filter A pool or spa water filter that uses a replaceable porous element made of paper or polyester as its removal system.

Catalyst Any substance of which a fractional percentage notably affects the rate of a chemical reaction without itself being consumed or undergoing a chemical change. Most catalysts accelerate reactions.

Cathode The negative electrode that attracts positively charged cations. The negative pole of an electrolytic system.

Caulking Material (usually silicone) used to fill a gap in a joint and provide a waterproof seal.

Caustic Common name for caustic soda or any compound chemically similar to caustic soda. Not commonly used in swimming pools and spas.

Cavitation The formation of partial vacuum when pump capacity exceeds water replacement supply. The formation and sudden collapse of vapor bubbles in a liquid, usually resulting from low local pressures, as on the trailing edge of a propeller.

Centrifugal Pump A pump consisting of an impeller fixed on a rotating shaft and enclosed in a casing or volute and having an inlet and a discharge connection. The rotating impeller creates pressure in the water by the velocity derived from the centrifugal force.

CFM Acronym for cubic feet per minute. A term used to describe the amount of air that an air blower will move. It is sometimes used to describe the amount of water moving past a point in a circulation system.

Channeling Refers to the non-standard flow of water through a D.E. or sand filter wherein the liquid follows the pathway of least resistance rather than passing uniformly throughout the medium bed. Channeling does not permit uniform filtration of the water passing through the filter.

Check Valve A mechanical device in a pipe that permits the flow of water or air in one direction only.

Chelate Pronounced KEY-late. Also called sequester. It is the process of preventing metals in the water from combining with other components in water to form colored precipitates that stain pool walls and bottom or produce colored water.

Chemical Feeder Any of several types of devices that dispense chemicals into the pool or spa water at a predetermined rate. Some dispense chlorine or bromine while other dispense pH-adjusting chemicals.

Chloramines Undesirable, foul-smelling, body-irritating compounds formed when insufficient levels of free available chlorine react with ammonia and other nitrogen-containing compounds (swimmer and bather waste, fertilizer, perspiration, urine, etc.). Chloramines are still disinfectants but they are a much weaker, ineffective form of chlorine. Chloramines are removed by superchlorination or shock treating.

Chlorinator A mechanical or electrical device for dispensing chlorine at a controlled rate. Most often a canister or floater filled with tablets of chlorine.

Chlorine A term used to describe any type of chlorine compound used as a disinfectant in swimming pool and spa water or to kill, destroy or control bacteria and algae. In addition, chlorine oxidizes ammonia and nitrogen compounds (swimmer and bather waste).

Chlorine Demand The amount of chlorine necessary to oxidize all organic matter (bacteria, algae, chloramines, ammonia and nitrogen compounds) in the pool or spa water.

Chlorine Generator An electrical device that generates chlorine from a salt solution in a tank or from salt added to the pool water.

Chlorine Lock This is a term that implied that there could be so much cyanuric acid (stabilizer or conditioner) in the water that the chlorine would be all "locked up." This is not true.

Chlorine Neutralizer A chemical solution used to make chlorine harmless. Used in test kits to counteract the bleaching effect of the chlorine or bromine in order to increase the accuracy of pool water tests. Sold as chlorine and bromine neutralizer, it is used to destroy excessive amounts of chlorine or bromine so the high levels will not affect swimmers. Chemicals used for this are sodium thiosulfate, sodium bisulfite, sodium metabisulfite, sodium sulfite, hydrogen peroxide and Vitamin C.

Chlorine Residual The amount of chlorine left in the pool or spa water after the chlorine demand has been satisfied.

Clarifier – also called coagulant or flocculant – A chemical compound used to gather (coagulate or agglomerate), or to precipitate suspended particles so they may be removed by vacuuming or filtration. There are two types: inorganic salts of aluminum (alum) or water-soluble organic polyelectrolytes.

Clarity The degree of transparency of the water.

Cloudy Water The visible effect in water created by material in suspension. Also called turbidity. A condition of the water due to the presence of extremely fine particles in suspension that can not be trapped by the filter because they are too small. Adding a clarifier such as an organic polymer or alum will coagulate the particles and make the filter more efficient.

Coagulant An organic polyelectrolyte used to gather (coagulate) suspended particles in the water.

Colorimeter A device used in analysis in which a fairly broad band of radiation or color, usually in the visible wavelength, is used. For example, the determination of chlorine in water by using the DPD method uses a visual comparison of samples and standards. Other testing techniques use a photometer or light detector.

Combined Chlorine Undesirable, foul-smelling, body-irritating compounds formed when insufficient levels of free available chlorine react with ammonia and other nitrogen-containing compounds (swimmer and bather waste, fertilizer, perspiration, urine, etc.). Combined chlorine is still a disinfectant but it is a much weaker, ineffective form of chlorine.

Conditioner See cyanuric acid.

Controller A device that automatically executes the decision making necessary to determine the proper adjust of a chemical parameter. Controllers are currently capable of automatically adjusting pH and sanitizer levels in water.

Coping The cap or top lip on the pool or spa wall that provides a finishing edge around the pool or spa. It can be formed, cast in place or precast, or pre-fabricated of extruded aluminum or rigid vinyl. It may also be part of the system that secures a vinyl liner to the top of the pool wall.

Copper It is one of nature's elements. It is also used for various parts of equipment and plumbing in swimming pools and spas. Corrosive water caused by misuse of chemicals, improper water balance or placing trichlor tablets in the skimmer can cause copper to be dissolved from the equipment or plumbing and deposit the precipitates on hair, fingernails or pool walls. High levels of copper also cause green water. Copper is also used as an algaecide. Maximum level about 0.2 ppm.

Copper Algaecide A chemical compound that contains the element copper. Copper sulfate ( ) was one of the original copper algaecides. Too much copper in the water can cause green-colored stains. Newer copper algaecides contain an ingredient that prevents the copper from staining but does not affect copper's ability to kill algae. These special copper algaecides are called chelated copper algaecides.

Corrosion The etching, pitting or eating away of the pool or spa vessel or equipment. Caused by improper water balance, misuse of acid or acidic products or from "soft" water.

Coupling A plumbing fitting that is used to connect to pieces of pipe.

COVERS:
Hard top cover A cover used on pools, spas and hot tubs that rests on the lip (coping) of the pool or spa deck, not a flotation cover, used as a barrier to swimmers and bathers, for maintenance and thermal protection.

Winter cover A cover that is secured around the perimeter of a pool, spa or hot tub that provides a barrier to bathers and debris when the pool, spa or hot tub is closed for the season.

Solar cover A cover that when placed on the water's surface of a pool, spa or hot tub, increases the water temperature by absorption and transmission of solar radiation, reduces evaporation and prevents wind-borne debris from entering the water.

CPVC A modified form of polyvinyl chloride, a synthetic resin that is composed of polymerized vinyl chloride and that, when plasticized or softened with other materials, has some rubber-like properties. A chlorinated polyvinyl chloride has more chlorine atoms per repeating monomer unit than does the polyvinyl chloride molecule. This extra chlorine is responsible for CPVC’s strength at high temperatures.

Cyanuric Acid – also known as conditioner and stabilizer – Chemically, conditioner is cyanuric acid, chemical formula. It protects chlorine in the water from being destroyed by sunlight. Minimum level 30 ppm. Too much does not slow down chlorine activity or effectiveness. Does not protect bromine from sunlight.

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z