AG: Above ground pool
Air Leak: happens when connections on the suction side are not airtight. Pool pumps need to create a vacuum to work properly. Air leaks can be dangerous by causing high pressures which can damage the pump, filter, or both. Aerated water can cause foam.
Algae: small plant life which grows in pool water. They are slimy in texture. Yellow and black algae are the hardest to kill.
Algaecide: a strong chemical which kills algae and deters its proliferation.
Alkalinity: a measure of how stable the pH is. (See total alkalinity)
Alum: aluminum sulfate, commonly called floc. It is used to help clarify water. It causes small particles to group together so they can be caught in the filter. Alum lowers the pH of the water.
Aluminum Sulfate: see Alum.
Automatic pool cleaner: device which cleans debris in the pool automatically.
Backwash: a means of cleaning which reverses the flow of water through the filter, forcing water and dirt out a waste line. This is done by adjusting the backwash valve to the backwash position. NOTE: Never adjust this valve while the pump is running.
Ball valve: It is used to regulate the flow of water and to shut off skimmers, drains, and other lines in order to vacuum or run a spa or water feature.
Biguanide: a sanitizer which is part of a non-chlorine pool water treatment system. Most chemicals used with chlorine are incompatible with Biguanide sanitizers, and vice versa. The recommended shock for Biguanide treated pools contains hydrogen peroxide.
Broadcasting: distributing chemicals in a pool by scattering them over the surface of the water.
Bromine: a sanitizer similar to chlorine, commonly used in spas. Very effective against bacteria, but it cannot be stabilized, so it is susceptible to deterioration by sunlight. When it combines with ammonia compounds, it is still an effective sanitizer, unlike chlorine.
Calcium Hardness: a measure of the level of calcium salts in the water. Helps determine how scaly or corrosive the water is. It is especially important to monitor in pools with a plaster finish.
Cartridge Filter: a filter with a pleated element which traps debris. It looks like a giant oil filter.
Chelating Agent: a chemical which binds to metals. It is used to prevent metal staining and discolored water.
Chlorine: a sanitizer and an oxidizer. As a sanitizer it kills bacteria in pools. As an oxidizer, it burns off organic matter and kills algae.
Chloramines: smelly organic byproducts caused by mixing ammonia with chlorine. It is cured by proper sho
Circulation: the flow of water in a swimming pool. Ideally, the circulation of your pool should have no areas of stagnant water.
Clarifier: chemical used to remove haze from water, usually works by causing small particles to join together so the filter can pick them up.
Coagulating Agent: see Flocculating agent and Clarifier
Coping: the material which joins the pool to the deck. It can be made of concrete, aluminum, plastic, brick, or wood. Commonly, concrete is used on concrete pools and aluminum is used on vinyl pools.
Cyanuric Acid: it stabilizes chlorine in the water. It can be a part of chlorine, or it can be added separately if you are not using stabilized chlorine. It helps deterioration of the chlorine by heat and sunlight. Avoid high levels of cyanuric acid (over 75 parts per million) which can cause discoloration, odors, and other problems.
DE: Diatomaceous Earth: a white powder commonly used to filter water. DE is added to the skimmer as it goes into the filter. It coats the elements. The earth does the filtering, not the elements. When the DE is dirty, the system is backwashed and new DE must be added to the filter. DE is a fossil material.
Defoamer: a chemical which reduces and/or eliminates foam by popping bubbles. It is squirted over the surface of the water.
Directional Fitting: An “eyeball” type device which attaches to the pool return so that water can be directed a certain way.
Discoloration: presence of unusual colors in the water, commonly clear green or brown.
Enzymes: they break down oily, gooey substances and convert them to water and carbon dioxide.
Fiber Optics: lighting system which has light generated at a remote source. Light is then transmitted along fibers.
Filter: tank which is used to filter fine debris out of pool water. Some types of filters are Cartridge, Diatomaceous Earth (DE), Regenerative DE, and sand.
Filter cycle: Length of time between cleaning, or backwashing, the system until it has to be done again.
Flocculating Agent: It is added to water to coagulate particles that cause haze. See Alum and Clarifier.
Gizzmo®: a hollow, collapsible, plastic fitting used to plug the skimmer. If ice forms in the skimmer, the Gizzmo® can absorb the expanding ice. It is green and looks like a thermos bottle.
Haze: “cloudiness” in water, caused by very small floating particles. See Turbidity.
Hydrogen Peroxide: an oxidizer used with Biguanide systems. It is typically used once per month.
IG: in ground pool.
Ionizer: a device which generates copper and/or silver ions needed to kill bacteria.
Organic Waste: debris such as microorganisms, perspiration, urine, etc. which needs to be burned up or oxidized regularly to prevent haze, algae, chloramines, etc.
Oxidizer: a chemical which burns up organic matter. See Organic waste.
Ozone: a form of oxygen which disinfects and deodorizes. It is generated and entered into the pool water by an ozonator.
pH: potential hydrogen. A measure of how acidic or basic the water is. pH of 7.0 is neutral. Pool water should be kept slightly basic, pH 7.2 – 7.8.
Pool surfaces: not to be confused with water surfaces, refers to the walls and floor of a pool. Some common surfaces are fiberglass, plaster, painted concrete, vinyl, and tile.
Pool types: Above ground, AG; in ground, IG.
Pressure Gauge: round dial located on backwash valve or on top of the filter. It indicates the pressure, in pounds per square inch, inside the filter. Then the pressure reads 10psi or more above what it did when the filter was freshly cleaned, then the filter needs to be cleaned.
Priming: filling the strainer or vacuum hose with water to help the pump push air out of the lines. If the pump won’t prime, a full flow of water to the pump is being stopped by an air leak or restricted by clogged lines or baskets.
Pump: moves water through the filter and around the pool.
Returns: the point at which water returns to the pool after passing through the filter.
Sand Filter: a filter which uses sand to filter pool water.
Sanitizer: a chemical used to kill bacteria. Generic names: Bromine, Biguanide (pronounced BY-GWAN-EYED), and chlorine.
Sequestering Agent: a chemical which bonds with metals so they can’t cause staining or discoloration. See Chelating Agent.
Shock: an oxidizer which burns off the organic wastes which cause cloudiness and algae. It is a generic term for a chemical used to oxidize organic wastes.
Skimmer: white, box like compartment on the side of the pool which automatically sifts the top few inches of water and removes debris and oily films. It contains a removable basket which needs to be cleared of debris periodically.
Strainer: a basket in front of the pump which keeps small debris from reaching the pump’s impeller area. It must be cleaned periodically.
Solar Heating Coils: accessory tubes through which water warmed by the sun heats the pool.
TDS: Total Dissolved Solids. A measure of the solids dissolved in the water. A high level of solids interferes with sanitizer effectiveness.
Tetraborate compound: a generic term for any chemical commonly used to treat and prevent pink slime, water mold, and algae.
Leaf Vacuum: it is powered by a garden hose. It is not the pool’s vacuum system. Debris swirls into a nylon bag on top of the leaf vacuum.
Leaf Rake or Scoop: it is like a surface skimmer but has a bag for picking up leaves.
Surface Skimmer: plastic, flat, mesh net skimmer used to scoop up floating debris.
Telescope Pole: adjustable length pole can attach to the vacuum cleaning head and hose, or to a brush, scoop, or skimmer.
Total alkalinity: a measure of the stability of pH. A low total alkalinity will cause to pH to fluctuate drastically when ever small amounts of acid or base are added to the pool water. A high total alkalinity will make the water more susceptible to scale and high pH. See Alkalinity.
Vacuum Hose: used to vacuum debris from the floor and slopes of the pool. It attaches to the vacuum head on one end and the vacuum plate on the other.
Vacuum plate: provides a vacuum sealed connection for the vacuum hose allowing debris to be caught in the skimmer basket rather than the pump strainer basket.
Valve, Multiport: a lever controlled chamber with a number of settings to allow you to backwash.
Valve, Slide: a manually controlled valve with two settings used to direct pool water flow.
Valve, Equalizer: device used in some pools where the main drain line is plumbed into the skimmer. It varies the flow from the skimmer and main drain. It is usually adjusted before vacuuming.
Water Mold: a type of bacteria used in nasty looking pool water. It is white gray or pink in color. It is very slimy and difficult to eliminate.