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custom inground pool

Need to know what a term means? This glossary covers all aspects of swimming pools, pool water, swimming pool problems, water problem, pool chemicals, pool water balance, swimming pool supplies and pool accessories. Contact us if you need further assistance 410-956-3630.

Microscopic plants capable of rapid reproduction.

Products that prevent or control algae growth.

Anti Foam
A chemical added to the water to make the suds or foam go away. These products do not remove the source of the sudsing. Most often, the water must be drained and refilled to remove the soaps, oils and other causes of foaming. Shocking and superchlorination may help prevent foaming.

Available Chlorine
The amount of chlorine, both free and combined in the pool water that is available to sanitize or disinfect the water. Some- times called residual chlorine.

The process of thoroughly cleaning the filter by reversing the flow of water through it with the dirt and rinse water going to waste.

Microscopic organisms, some of which are harmful to bathers.

Balanced Water
The proper ratio of mineral content and pH that prevents pool water from being corrosive or scale-forming.

A halogen element alternatively used as a sanitizer for pools.

Calcium Hardness (CH)
The amount of dissolved calcium in water. Ideal range 175 - 275 ppm depending on surface type.

A halogen element, compounds of which are widely used in pool water sanitation.

Irritating compounds formed by the combination of nitrogenous compounds and free chlorine. Nitrogenous compounds are introduced into the water by urine, perspiration, cosmetics, suntan oils, etc.

Chlorine Demand
The amount of a free available chlorine residual needed to destroy organic contaminants and establish a stable residual for effective sanitation.

Chlorine Residual
The amount of total chlorine in pool water.

Combined Chlorine (Chloramine)
Chlorine which is bonded to other compounds.

Dry Acid
Product used to lower pH and total alkalinity; preferred over muriatic acid (HCl) for handling, storage and safety issues.

Free (Available) Chlorine
Chlorine in a form capable of bacteria and algae destruction. Preferred range: 1.0 to 3.0 ppm.

A way to measure the acidity or alkalinity of water. This is the most important part of chemical balance. (Ideal range 7.4-7.6)

Parts Per Million, a measurement for chemical concentration.

Tablets, powder or liquid material for use in water testing.

Coarse calcium or silicate deposits on swimming pool wall, floors and circulation plumbing, especially in heat exchangers.

Saturation Index
A value based on water temperature, total alkalinity, calcium hardness and pH. The value predicts the tendency of pool water to be corrosive, neutral or scale-forming.

Shock Treatment
Adding an oxidizing compound to the pool water to chemically break up (oxidize) contaminants such as suntan oils, cosmetics, perspiration and windblown dirt.

Stabilized Chlorinating Products
Form of chlorine used to sanitize pool water. Favored for its economy and ability to remain active in strong sunlight.

Cyanuric acid; a compound that prevents the dissipation of chlorine residuals by sunlight.

Super chlorination
Adding enough chlorine (3 to 5 times usual dose) to destroy chlorine demand compounds and combined chlorine.

Total Alkalinity (TA)
The amount of the alkaline components in water. TA acts as a buffer against rapid pH fluctuation. (Ideal range 125-150)

Undesirable Compounds
Substances introduced in the water by people or the environment that interfere with ideal pool conditions.