Glossary Pool Terms

(Based on the book Cruising Through Pool Care the Wise Way by Marry Wise)
Acid: Refers to several things: what the level of pH is of the water – how corrosive. Also, The stuff you put in the pool to make the water lower in pH or total alkalinity, to make it less scaling, like that white stuff that forms in your coffe pot. Muratic or dry acid is used.
Air Relief valve: The little screw-type dealie on the top of the filter by the pressure gauge, which bleeds off air after you turn a pump back on
Algae: Plant-like organisms that grow in the pool and make it yucky when there is not enough sanitizer in the water. The little suckers come in several types-green, blue-green or black, mustard yellow and pink slime, which can also be a fungus or bacteria.
Algae Brush: A metal brush used to brush algae, knocking off the top of the sopre and allowing chlorine to get inside to kill it. A good item to use to work off excess aggression.
Algaecide: Chemical product that surrounds the algae cell and fools it, causing it to open up so the chlorine can kill it better. An aid to chlorine to kill algae.
Alkalinity Increaser: Stuff you add to increase the total alkalinity-sodium bicarbonate- same thing as baking soda!
Automatic Controller: Pool Equipment feature for pools and spas that controls their functions automatically, usually via computerized controls- can sometimes be equipped to give the man of the house another remote to play with.
Automatic Pool Cleaner: A device to automatically vacuum pools, one of the greatest blessings for a pool owner known to man (or woman).
Backwash: Reverse the flow of water through a pool filter to clean it out when it becomes clogged.
Backwash Valve: The valve on a pool you use to change the function of the pool plumbing to the backwash, or cleaning out, mode on a pool filter.
Balance: In terms of pools, the proper proportions of chemical levels for several different factors so that the pool is not corrosive, not scaling, not irritating to the swimmer, not damaging to surfaces and equipment, not staining, and is making maximum use of the sanitizer to keep it clean and free of algae.
Ball Valve: Type of valve to control water flow with a ball device in it, a newer type made to be easily fixed with replaceable parts.
Biguanide : A product for sanitizing pools that uses cell destruction to kill bacteria, usually sold in a  system with other products to maintain a pool.
Breakpoint Chlorination: adding enough free available chlorine to pool water to oxidize all the organic matter, ammonia, and nitrogen compounds, twice a normal shock.
Bromamines: Bromine tied up with ammonia, not doing its job of killing bacteria in a pool or spa.
Bromine: A chemical product used to sanitize pools or spas.
Calcium carbonate, Calcium scale or scale: deposit that forms as crystals and clogs up plumbing and filters and forms as a rough deposit on pool walls when the total alkalinity, pH,and/or calcium hardness is too high in pool or spa water.
Calcium Chloride: Chemical product used to raise the calcium hardness level in pools, also referred to as hardness increaser.
Calcium Hardness: the amount of minerals in poll water.
Calcium Hypochlorite: Chlorine shock product for pools
Cartridge: Cylinder with pleats all around it used to filter water in a cartridge-type pool filter.
Cartridge Filter: pool water filter using cartridges inside to filter the water.
Chloramine: Chlorine tied up with ammonia not doing its job of killing bacteria and oxidizing organic waste- will sometimes make the pool smell funny.
Chlorine: Chemical product used to sanitize pools, comes in several forms and strengths- free chlorine is the available chlorine in the water doing it’s job, combined chlorine is the chlorine tied up not doing its job and total chlorine is the measure of both of them.
Chlorinator: Container in which chlorine is placed to feed chlorine to the pool water on a continuous basis- can be an automatic feeder plumbed into the pool equipment or floating in the pool.
Clarifier: Chemical product that collects particles in a pool too small to filter out makes them into bigger clumps so they will trap out in the pool filter and clear the water.
Coping: The top edge around the pool, sometimes designed as a decorative feature using rock, brick, coping stones, slate or other materials.
Cooper: one of the metals that may be found in pool water-stains the pool with splotchy blue or aqua stains if precipitated out on the wall of a white plaster pool
Corrosive: Water condition that is too acid, and will cause metal parts of pool equipment to dissolve, and etching of pool walls in a gunite pool or wrinkling of liners in a vinyl pool.
Cyanuric Acid: Also called conditioner or stabilizer-product added to pool water to hold chlorine in the water better so that it does not dissipate as quickly from sunlight. Sometimes also used as an additive in some forms of pool chlorine.
DE: Also known as diatomaceous earth-a product composed of tiny fossilized sea organisms used to coat the grids in DE filter to filter the pool water
DE Filter: Filter using grids inside coated with DE to filter the pool water.
Deck: The Walkway around a pool.
Diverter Valve: Plumbing valve used to change the direction of the flow of pool water.
DPT Test Kit: Type of pool water test kit using DPD tablets to test pool water.
Dry Acid: A dry form of acid used to lower pH and /or total alkalinity in pool water.
Filter: A piece of pool equipment used to filter the pool water, cleaning it and recirculating it back to the pool.
Float Valve: Floating valve in the bottom of a skimmer to control the water flow.
Gate Valve: Valve that twists on and off to control water flow.
Grid: Also called filter grid or filter element- device in a DE filter that when coated with DE traps particles in the water, filtering and cleaning it for return to the pool.
Head Pressure: Technical term describing the pressure and resistance of water flowing through a pipe-used to plan the correct hydraulic system in a pool.
Heater: Pool equipment item for heating pool water.
Hose: Pool hose used to attaché to a vacuum head to manually vacuum a pool.
Hypochlorous Acid: The bacteria-Killing form of chlorine in pool water, the most powerful form of disinfecting chlorine-it’s what you want to be doing the job of killing bacteria and oxidizing organic waste so the pool is safe and algae-free to swim in.
In Floor Pool Vacuum System: a built vacuuming system in a pool, which suctions out debris through floor fittings and automatically vacuums the pool through these floor suction thingies.
Inlet: The PVC fittings in the pool through which water returns from the filter, also called return inlets.
Ion-generating System: Pool sanitizing that uses copper and silver ions to help sanitize the pool, but also requires some chlorine shock. A metal sequestering product should be used with it  due to danger of staining from this system.
Iron: Metal that is undesirable to have in pool water due to the possibility of staining-stains brown or rust color.
Jandy™/Ortega™/3-Port Valve: All names for a type of valve that controls water flow with multiple positions.
Lateral: One of a series of finger-like things in the bottom of a sand filter that forces the water through the sand bed to filter it.
Leaf Net:Flat Pool net that goes on the end of the pool pole to skim debris off the surface of a pool or spa.
Leaf Rake:Deep net that goes on the pool pole to skim debris off the bottom or surface of a pool or spa.
Main Drain:The Grate for the suction line at the bottom of a pool or spa- should now be equipped as a dual drain with split suction or with an antivortex device to avoid hair or body entrapment
Modular Media:Large Capacity cartridge Filter
Muriatic Acid: Dilute hydrochloric acid used in pool water to lower pH and/or total alkalinity.
Non-Chlorine Shock: A  Chemical used to shock pools or spas that does not contain chlorine but can oxidize organic waste.
O-Ring: Rubber ring used on pool equipment in various places to better seal an opening or lid.
Oxidation: The process of burning up and getting rid of ammonia compounds, nitrogen compounds, and swimmer waste in pool water by shocking it with chlorine or non-chlorine chemicals , so that they do not disable the killing power of the chlorine.
Ozone: A Molecule with 3 atoms of oxygen to oxidize contaminants in pool water using a device called an ozonator.
pH Potential hydrogen ion concentration or simply a term used to tell how acid or basic the water is in a pool or spa. It is the most important factor of pool water balance.
Pole:Swimming Pool pole used as a multipurpose maintenance item to connect the brush, or vacuum head, or leaf net, or leaf rake to in order to maintain a pool.
Pool Brush: Long plastic brush that attaches to the pole to brush the wall, steps and tile in maintaining a pool.
Pressure Gauge: Gauge on top of the filter to measure the operating pressure of the filter and indicate when it needs to be cleaned.
Prime: To make a pool pump run as it is intended, full of water, not dry, which can burn it out.
PSI: A Measure of pressure, stands for pounds per square inch.
Pump: The piece of pool equipment that, with the pool motor, moves water from the pool to the equipment and back.
Pump Basket:Basket in the pool pump that traps larger debris from water coming into the pump and filter needs to be emptied about once a week.
Q, R
Reagent: Chemical used to test pool water.
Salt-Generating chlorine System: A system used to sanitize pools with a piece of equipment that makes salt into chlorine in the pool.
Sand Filter: Pool Filter that filters water using a bed of sand in a filter tank with laterals in the bottom.
Sanitizer: A chemical used to sanitize pools-Kill bacteria and oxidize organic waste.
Sanitizing:Killing bacteria and oxidizing organic waste in pool or spa water.
Scaling:Prone to form scaly crystal deposits in pool equipment, plumbing or on walls, found in pools with water too high in pH, total alkalinity, and /or calcium hardness.
Sequester: To tie up metals and scaling products in pool water before they plate out on the surface wall of the pool, staining or scaling it.
Shock: To add extra chlorine to burn out swimmer wastes, make combined chlorine active again, kill bacteria and add a residual of chlorine to do a good job of sanitizing the pool again, gets rid of “chloramines”, the “little stinkers” that make pools smell funny.
Sight Glass:A clear viewing window that allows you to see pool water as it backwashes so you can tell when the water has finished backwashing, is clear and the filter is ready to be returned to filtering again.
Skimmer: The hole in the side of the pool containing a basket with suction plumbing line underneath designed to skim surface debris off the top of the pool before it falls to the bottom.
Skimmer Basket: the basket in the skimmer that traps the stuff that flows into it.
Skimmer Lid: The lid that covers the skimmer hole in the deck so nobody steps in it and breaks his or her leg
Skimmer Weir: The little flap over the skimmer opening in the pool that keep the stuff from floating back out of the skimmer basket into the pool.
Soda Ash: Chemical to raise pH, also called sodium carbonate.
Sodium Dichlor: A Shortened name for a fast-dissolvong granular chlorine product.
Sodium Hypochlorite: Liquid chlorine also called liquid bleach.
Test Kit: Kit designed to use to test the pool water with strips, reagents, or dpd tablets.
Test Strips: Strips used to test pool water.
Titrant: Reagant used to drip into pool water drop by drop to test the water or method of testing through liquid regents that drop into the water in a test container.
Total Dissolved Solids:Measure of all the stuff dissolved in pool water.
Trichlor: Short name for stabilized chlorine tablets used to sanitize pool water.
Vac Head: Vacuum head used to attach to the pool pole to manually vacuum the pool.