FROG Water Care Experts Glossary of terms

A long-handled aluminum pole, which extends in length. Various pool-cleaning tools, such as brushes or vacuums, may then be attached.

Chemically treated strips that have the appropriate amounts of reagents on them. Simply dip them into the water and read the reactions. These strips can test free available and total chlorine, bromine, pH, calcium hardness, total alkalinity and cyanuric acid. These strips are not to be used to replace more accurate DPD test kits. They can be used in conjunction with more accurate kits.

A generic term for a chemical commonly used to treat and prevent pink slime, water mold and algae.

A test used for acid and base demands, total alkalinity and calcium hardness. It creates an end-point reaction by adding drops of the reagent to elicit a change in the sample's color. The number of drops required correlates with the measurement. Sanitizer tests are available using this method.

A measure of total alkaline substances dissolved in the water and of the water's ability to resist pH change (stability). If too low, the pH tends to bounce very erratically. If too high, pH resists adjustment and the water is more susceptible to scale and high pH. Recommended range = 80-150 ppm. See Alkalinity.

A measure of both "free chlorine" and "combined chlorine" in pool water.

A measure of the amount of dissolved matter in the water. A high level of solids (1500 ppm and higher) interferes with sanitizer effectiveness. Maximum amount in pools is 2500 ppm. Maximum for spas is 1500 ppm over starting TDS. The only way to effectively lower TDS is to drain part or all of the water and replace it.

A slow-dissolving, tableted or granular, stabilized organic chlorine compound providing 90% available chlorine. Used for regular chlorination, but must be dispensed using a floating feeder or an in-line feeder (chlorinator). Trichlor contains an ingredient that prevents the chlorine from being controlled by the ultraviolet (UV) rays of the sun. Trichlor has a pH of 2.8, and regular trichlor tablets should not be placed in the skimmer.

The cloudy condition of the water due to the presence of extremely fine particles in suspension that cannot be trapped by the filter because they are too small. Adding a clarifier, such as alum, will coagulate the particles and make the filter more efficient.

Used to test the amount of cyanuric acid in the water. The reagent causes a cloudiness in the test water. Measurement is obtained by comparing the test water's visibility (the degree of clarity of a dot in the test vial) to the test manufacturer's chart.

The period of time (usually in hours) required to circulate a volume of water equal to the volume of water contained in the pool or spa. For example, pool capacity in gallons, divided by pump flow rate in gallons per minute (gpm), divided by 60 minutes in 1 hour, will give hours for 1 turnover.