Acid: A chemical which lowers pH when added to water. Sodium bisulfate (dry acid) is a very strong acid.
Algae: Microscopic aquatic plant life which can grow on pool surfaces or float free in the waters. Though harmless, algae discolor the water and indicate improper sanitation.
Algaecide: A chemical compound used to kill or inhibit the growth of algae.
Automatic Cleaner: A vacuum that can be programmed to automatically clean pool and spa wall and floors. The timer should be timed to start cleaning at least one hour after the pump has begun and to finish before pump turns off.
Base: A chemical which raises pH when added to water.
Backwash: Reverses the water flow in the filter. Water enters through a return valve and exits out a designated line- some times into the city's sewer or a holding container. This technique reduces filter pressure by cleaning the filter material. Do not backwash a cartridge filter.
Bacteria: One-celled organism; some of which cause disease and/or infection. Without proper sanitation, pool water and pool surfaces are perfect breeding grounds for bacteria.
Bromine: A very strong oxidizer in the same chemical family as chlorine-elemental bromine is a dangerous reddish-brown liquid not recommended for home use.
Bromine Demand: The amount of active bromine required to destroy and oxidize bacteria, algae and other organic compounds. (When the demand is satisfied the water is considered sanitized and safe to use)
Buffer: A chemical which when dissolved in water, will cause water to resist pH change. TOTAL "A" is a buffer.
Calcium Hardness(CH): The quantity of calcium dissolved in water. High levels promote scale and cloudy water. Lower levels result in a corrosive condition.
Cartridge Filter: A filter having one or more cartridges, each containing a tightly folded, or pleated, finely meshed material that traps dirt particles as the water moves through the filter chamber. Never backwash cartridge filter.
Chlorine: A common oxidizer and sanitizer for swimming pools.
Circulation System: The pipes through which water flows - from the pool/spa to the skimmer and drain to the pump to the filter to the heater and back again to the pool/spa.
Clean Filter Pressure: The pressure reading when the filter is known to be clean and free of obstructions.
Corrosion: The removal of metal from copper or other metal surfaces in a destructive manner. Corrosion can be caused by low pH - low total alkalinity, low calcium hardness or a combination of all three. Very high water velocity through copper piping or heat exchangers can be corrosive.
Debris: Any foreign object in a pool or spa.
Diatomaceous Earth Filter (DE): A filter containing diatomaceous earth, a natural material that is extremely porous and tacky. In these filters, interior grids are coated with DE which collects dirt as the water passes through the filter.
Disinfect: To kill and inhibit the growth of harmful bacteria and virus in pool water.
Filter: The piece of equipment that helps clean the pool or spa water of impurities.
Filter Pressure: The pressure that helps push water through the filter media. If a filter's pressure rises above 8 to 10 pounds over a "clean" pressure reading, you should backwash the filter.
Flocculant: A chemical that can be added to the water to combine or coagulate small dirt particles into larger ones. Floccuclants are typically used with sand filters, which can allow some smaller particles of dirt to escape.
Hand-held Skimmer: A net made of fine mesh material attached to a pole and used to remove large debris from the pool and spa water surface.
Heater: A natural gas or electronically fired device that heats the water on its way back into the pool or spa.
Impurity: Any foreign object in the pool or spa water.
Motor: A device that converts electrical energy to mechanical energy in order to power the pool/spa pump.
Nylon Bristle Brush: A brush attached to a pole used to scrub the walls of a plaster pool and spa.
O-ring: A small rubber ring found in filter valves and wedged tightly between the lid and the main opening to the pump and its strainer pot. It ensures a tight seal and, therefore, the proper pressure in the pump or filter.
pH: The measurement of the relative acidity and basicity(alkalinity) of water. pH is measured on a scale that runs 0 to 14. pH values below 7 are acidic and values higher than 7 are basic. Pool water should be between 7.2 and 8.0.
Pump: The piece of equipment in your swimming pool and spa that pulls the water into the circulation system via the skimmer, gutter and main drain. The pump includes a strainer pot, or a hair and lint trap, to collect material that was small enough to pass through the skimmer or other strainer elements.
Sand Filter: A filter containing sand and gravel as its purifying mechanism. As water flows through the filter, dirt becomes attached to the rough edges of the sand and gravel particles.
Skimmer: An opening in the pool wall, usually at the water line, which draws the water into the plumbing system. Skimmers are also used to provide suction for vacuums.
Strainer Pot or Hair and Lint Trap: Located in the pump, this is a basket made of mesh material that collects any dirt and debris that have passed through the skimmer, gutter or main drain.
Surface Areas: The total amount of surface on the material within a single cartridge of a cartridge filter. The larger the surface areas, the more dirt the filter can trap.
Tile Soap: A pH balanced and non-foaming cleaner specifically designed to remove scum, oil and dirt from pool or spa walls and tiles. Different surfaces require different types of soaps.
Vacuum: A cleaning device moved along pool and spa walls and floors that suck up the dirt and passes it directly to the filter or a spot outside the pool and spa.
Water Balance: Term used to describe the interaction of pH, Total Alkalinity and Calcium Hardness, and their overall effect on your pool equipment, water quality and the pool itself.
Never vacuum to the backwash system.