A sour chemical substance that releases hydrogen ions with the ability to dissolve metals, neutralize alkaline materials and to combine with bases to form salts. Acid is used to lower (decrease) pH and total alkalinity of swimming pool and spa water. Examples are muriatic acid (hydrochloric) and dry acid (sodium bisulfate). All liquids with a pH lower than 7.0 are acidic or acid.
The gathering of fine, suspended matter in water into “flocs” or larger masses that then can settle and be filtered from the water.
Another method is the use of a Leaf Bagger, a product by Jandy Industries. Attached to a telescopic pole and a garden hose, the Leaf Bagger uses venturi action to suck leaves up into a large attached bag as you roll the unit over the leaves. It’s slow going, but you won’t have to stop to empty the bag too often.
Microscopic plant-like organisms that contain chlorophyll. Algae are nourished by carbon and use sunlight to carry out photosynthesis. They are introduced by rain or wind and grow in colonies producing nuisance masses. Algae are not disease-causing but they can harbor bacteria and they are slippery. There are 21,000 known species of algae. The most common pool types are black, blue-green, green and yellow or mustard. Pink or red colored algae-like organisms exist but are bacteria and not algae. Maintaining proper sanitizer levels, shocking and super chlorination will prevent their occurrence.
If you haven’t purchased a leaf rake, or a “drag bag”, as I sometimes call them, and are holding on to that flat “dip & flip” net that your builder gave you; you are creating your own hell. I strongly encourage the purchase of a nice leaf rake. There are also chemical products which are used to keep surface tension high, moving small debris to the sides of the pool. Another possible problem could be the condition of the weir in the skimmer; you know, that flapper gate thing. Make sure it is operating properly so that it creates a draw or “waterfall” into the skimmer basket. Also check that the water level is not so high that it is above the opening of the skimmer.
Lastly, you may need to trim some of those trees and bushes near the pool. My pool, for example, was specifically built with no vegetation anywhere within wind shot!
A class of compounds which will react with an acid to give a salt. A substance that creates a bitter taste and a slippery feel when dissolved in water. An alkali has a pH greater than 7.0 and is the opposite of an acid. Alkalis may include the soluble hydroxide, carbonate and bicarbonate salts of calcium, magnesium, potassium and sodium. A reaction between an acid and a base is called neutralization.
A measure of the pH-buffering capacity of water. Also defined as the water’s resistance to change in pH. Composed of the hydroxides, carbonates and bicarbonates in the water expressed in parts per million (ppm) or milligrams per liter (mg/L). One of the basic water tests necessary to determine water balance. The ideal range is from 60 parts per million (ppm) to 140 ppm.
Introduced into the water by swimmers as waste (perspiration or urine). Quickly forms foul-smelling, body-irritating chloramines – a disabled, less effective form of chlorine. See chloramines or combined chlorine.
A chemical added to the water to remove suds or foam. These products do not alleviate 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, super chlorination, clarifiers and enzymes may help remove the causes.
This term usually refers to liquid chlorine (sodium hypochlorite, NaOCl, 10-percent to 12-percent chlorine by weight). It is the same chemical used in laundry bleach but pool chlorine is 12-percent available chlorine while laundry bleach is about 5-percent to 6-percent available chlorine. A gallon of liquid chlorine contains about 1 pound of pure chlorine or is equivalent to 1 pound of gas chlorine.
By-products formed when bromine reacts with swimmer waste (perspiration or urine), nitrogen or fertilizer. Bromamines are active disinfectants and do not smell, although, high levels are body irritants. Bromamines are removed by super chlorination or shock treatment.
A common name for a chemical compound containing bromine that is used as a disinfectant to destroy bacteria and algae in swimming pools and spas. Available as a tablet or as sodium bromide, a granular salt.
Crystalline compounds formed in swimming pool and spa water when the calcium, pH and total alkalinity levels are too high. Once formed, the crystals adhere to the plumbing, equipment, pool walls and pool bottom. These crystals are better known as scale.
The calcium content of the water. Calcium hardness is sometimes confused with the terms water hardness and total hardness. Too little calcium hardness and the water is corrosive. Too much calcium hardness and the water forms scale. One of the basic water tests necessary to determine water balance. Minimum level 150 parts per million (ppm). Ideal range is 200 ppm to 400 ppm.
A compound of chlorine and calcium used as a disinfectant, sanitizer, bactericide, algaecide and oxidizer in swimming pool and spa water. It is available as a white granular material usually used for super chlorination or it is available as tablets used in a feeder for regular chlorination. It usually contains 65-percent available chlorine but is available as 70 percent and 75 percent also. Often referred to as cal-hypo.
Pronounced KEY-late. Also called sequester. It is the process of preventing metals in the water from combining with other components in the water to form colored precipitates that stain pool walls and bottoms or produce colored water.Pronounced KEY-late. Also called sequester. It is the process of preventing metals in the water from combining with other components in the water to form colored precipitates that stain pool walls and bottoms or produce colored water.
Undesirable, foul-smelling, body-irritating compounds formed when insufficient levels of free available chlorine react with ammonia and other nitrogen-containing compounds (swimmer and bather waste, fertilizer, perspiration, urine, etc.). Chloramines are still disinfectants but they are a much weaker, ineffective form of chlorine. Chloramines are removed by super-chlorination or shock treatment.
A term used to describe any type of chlorine compound used as a disinfectant in swimming pool and spa water or to kill, destroy or control bacteria and algae. In addition, chlorine oxidizes ammonia and nitrogen compounds (swimmer and bather waste).
A chemical solution used to make chlorine harmless. Used in test kits to counteract the bleaching effect of the chlorine or bromine in order to increase the accuracy of pool water tests. Sold as chlorine and bromine neutralizer, it is used to destroy excessive amounts of chlorine or bromine so the high levels will not affect swimmers. Chemicals used for this are sodium thiosulfate, sodium bisulfite, sodium metabisulfite, sodium sulfite, hydrogen peroxide and Vitamin C.
A chemical compound used to gather or to precipitate suspended particles so they may be removed by vacuuming or filtration. There are two types: inorganic salts of aluminum (alum) or water-soluble organic polyelectrolytes. Often referred to as a coagulant or flocculent.
Undesirable, foul-smelling, body-irritating compounds formed when insufficient levels of free available chlorine react with ammonia and other nitrogen-containing compounds (swimmer and bather waste, fertilizer, perspiration, urine, etc.). Combined chlorine is still a disinfectant but it is a much weaker, ineffective form of chlorine.
The cap or top lip on the pool or spa wall that provides a finishing edge around the pool or spa. It can be formed, cast in place, precast or pre-fabricated of extruded aluminum or rigid vinyl. It may also be part of the system that secures a vinyl liner to the top of the pool wall.
A chemical compound that contains the element copper. Copper sulfate was one of the original copper algaecides. Too much copper in the water can cause green-colored stains. Newer copper algaecides contain an ingredient that prevents the copper from staining but does not affect copper’s ability to kill algae. These special copper algaecides are called chelated copper algaecides.
A cover used on pools, spas and hot tubs that rests on the lip (coping) of the pool or spa deck, not a flotation cover, used as a barrier to swimmers and bathers, for maintenance and thermal protection.
A cover that, when placed on the water’s surface of a pool, spa or hot tub, increases the water temperature by absorption and transmission of solar radiation, reduces evaporation and prevents wind-borne debris from entering the water.
It protects chlorine in the water from being destroyed by sunlight. Minimum level 30 parts per million. Too much does not slow down chlorine activity or effectiveness. It does not protect bromine from sunlight.
A Diatomaceous Earth Filter is A filter designed to use diatomaceous earth (D.E.) as the filter medium. The D.E. is added through the skimmer when the pump is on. This deposits the D.E. on a grid, where it then becomes the filter medium.
The process of adding a chemical to the water to remove the residual chlorine. Chemicals used for this are sodium thiosulfate, sodium bisulfite, sodium metabisulfite, sodium sulfite, hydrogen peroxide and Vitamin C.
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, super chlorination, clarifiers and enzymes may help remove causes.
A white powder composed of fossilized skeletons of one-celled organisms called diatoms. The skeletons are porous and have microscopic spaces. The powder is added through the skimmer and deposits itself on a grid. The powder then becomes the filter medium.
A fast-dissolving chlorine compound containing sodium, chlorine and cyanuric acid (stabilizer or conditioner). It has a nearly neutral pH (pH 6.8) and is quick dissolving so it can be used for regular chlorination or super chlorination. Two types are sold. The anhydrous version provides 62-percent available chlorine and is more dangerous to store and handle. The dihydrate, which has 56-percent available chlorine, is much safer to store and handle.
Fine-spun filaments of glass which are available in a rope or mat form. When used in a process with polyester resins, catalysts and hardeners, fiberglass can be formed or molded into pools, spas and related shapes.
A device that removes undissolved or suspended particles from water by recirculating the water through a porous substance (a filter medium or element). The three types of filters used in pools and spas are sand, cartridge and D.E. (diatomaceous earth).
In essence, the material used in the filter to trap suspended dirt particles as the water is flowing through it. The polyester or paper used in making a cartridge filter element. The sand used in a sand filter. The D.E. (diatomaceous earth) used in a D.E. filter.
A chemical feeder whereby the chemical is placed in a container and the container is allowed to float around the pool dispensing the chemical. The chemical dissolves in the floater and is released into the water. Most often these are used for chlorine or bromine.
A chemical element used as a sanitizer and disinfectant in swimming pool water. The greenish gas is compressed and becomes a liquid under pressure. It is 2.5 times heavier than air and is highly toxic to humans if released.
A mixture of cement and sand sprayed onto contoured and supported surfaces to build a pool. Gunite is mixed and pumped to the site dry and water is added at point of application. Plaster is usually applied over the gunite.
The chemical elements either individually or collectively that constitute Group VIIA of the periodic table: namely, fluorine, chlorine, bromine iodine and astatine. Of these, only chlorine and bromine are used as disinfectant and sanitizers in pool and spas.
Drinking water term that indicates water that contains one grain per gallon – 17.1 parts per million (ppm) or milligrams per liter (mg/L) or higher of total hardness. The ideal range of hardness for pools and spas is 200 ppm to 400 ppm.
The amount of calcium and magnesium dissolved in the water. “Water” or “total” hardness refers to the total of the magnesium and calcium dissolved in the water. Calcium hardness refers to just the calcium. Measured by a test kit and expressed as parts per million (ppm). Proper range is 200 ppm to 400 ppm.
The universally accepted ranges for the chemical parameters for swimming pool or spa water. For instance, the ideal pH range is 7.4 to 7.6; the ideal chlorine level is 1.5 parts per million (ppm) to 3.0 ppm; the ideal total alkalinity is 80 ppm to 140 ppm depending on the sanitizer being used; the ideal hardness level is 200ppm to 400 ppm.
A water-sanitation device that uses electricity to generate metal ions which are dispersed in the water. It works by passing a low-voltage, DC current through a set of metallic (usually copper and silver) electrodes placed in line with the circulation equipment. The copper is an algaecide while the silver is a bactericide. This process does not remove swimmer waste.
Sodium hypochlorite solution, chemical formula usually provides 10 percent to 12 percent available chlorine; has a pH of 13 and requires that small amounts of acid be added to the pool to neutralize the high pH. Good for regular chlorination and superchlorination. It is the same chemical used for household or laundry bleach except that laundry bleach is about 5.6-percent available chlorine. One gallon of liquid chlorine 12.5 percent is equal to about one pound of gas chlorine.
A dry, granular chlorinating compound with an available chlorine content of 35 percent. It is rapid dissolving and should be used to superchlorinate vinyl-liner pools, painted pools or fiberglass pools as well as spas and hot tubs.
A measure of the amount of magnesium dissolved in the water. It is part of total or water hardness. It also causes scale if levels are too high. In tap water, magnesium hardness is about 25 percent of the total hardness and calcium is about 75 percent.
Usually refers to a plumbing fitting installed on the suction side of the pump in pools, spas and hot tubs. Sometimes called the drain, it is located in the deepest part of the pool, spa or hot tub. The Main Drain is unique in that it does not allow the water to drain to waste but rather connect to the pump for circulation and filtration.
A selected group of materials used in filters and filter devices to form barriers to the passage of certain solids or molecules that are suspended or dissolved in water. Media is the plural form of medium and refers to more than one type of barrier material. In the pool and spa industry, filters use either sand, polyester or diatomaceous earth (D.E.) as the media.
A chemical solution used to make chlorine or bromine harmless. Used in test kits to counteract the bleaching effect of the chlorine or bromine in order to increase the accuracy of pool water tests. Sold as chlorine and bromine neutralizer, it is used to destroy excessive amounts of chlorine or bromine so the high levels will not affect swimmers. The most common ones are sodium thiosulfate, sodium sulfite, sodium metabisulfite, hydrogen peroxide and vitamin C.
A term given to a class of chemical compounds that are used to oxidize or shock the water (destroy ammonia, nitrogen and swimmer waste). They contain no chlorine or bromine and do not kill living organisms. Swimmers may re-enter the water in only 15 minutes after adding a non-chlorine shock. Examples are monopersulfates, hydrogen peroxide and percarbonates.
Chloramines formed from the combination of chlorine and organic ammonia or nitrogen (swimmer waste, perspiration, urine, sweat, saliva, etc.) these are not considered disinfectants like inorganic chloramines.
To rid the water of ammonia, nitrogen compounds and swimmer waste (organic compounds). These organic compounds disable chlorine, are body irritants and have a foul smell. Removal is accomplished by superchlorination or by shock treating with a non-chlorine oxidizer.
A term used to indicate the level of acidity or alkalinity of pool water. Too low pH causes etched plaster, metal corrosion and eye irritation. Too high pH causes scale formation, poor chlorine efficiency and eye irritation. Proper range for pH in swimming pools is 7.4 to 7.6. It is always written with a lower case “p” and a capital “H.”
A mechanical device, usually powered by an electric motor, which causes hydraulic flow and pressure for the purpose of filtration, heating and circulation of pool and spa water. Typically, a centrifugal pump is used for pools, spas and hot tubs.
A type of organic compound in which the molecular structure includes a central nitrogen atom joined by four organic groups as well as to an acid radical. Cationic quaternary ammonium compounds adsorb on the cell walls of microbes and algae and react chemically with the negative charges carried by the cell walls. These chemical compounds of ammonia are used as algaecides and algaestats.
The amount of measurable bromine remaining after treating the water with bromine. The amount of bromine left in the pool or spa water after the bromine demand has been satisfied. Includes hypobromous acid (HOBr), hypobromite ion, free and total bromine and all combined bromine.
The amount of measurable chlorine remaining after treating the water with chlorine. The amount of chlorine left in the pool or spa water after the chlorine demand has been satisfied. Includes hypochlorous acid (HOCl), hypochlorite ion free and total chlorine and all combined chlorine.
A filter using sand or sand and gravel as the filter medium. The oldest (patented in 1790) method of improving water quality, generally using two layers of sand supported by an underbed layer of gravel.
The precipitate that forms on surfaces in contact with water when the calcium hardness, pH or total alkalinity levels are too high. This is the result of chemically unbalanced pool and spa water. Scale may appear as grey, white or dark streaks on the plaster, fiberglass or vinyl. It may also appear as a hard crust around the tile.
The extraneous or foreign matter which rises to the surface of the water and forms a layer or film there. It can also be a residue deposited on the tile or walls of the pool or spa. Sources of scum are soap, oil, deodorant, hair spray, sun tan lotion and various others.
A chemical that will combine with dissolved metals in the water to prevent the metals from coming out of solution (precipitating or causing stains). May also be a chemical that removes dissolved metals from water.
The practice of adding significant amounts of an oxidizing chemical (usually non-chlorine oxidizers such as sodium persulfate or potassium peroxymonosulfate) to the water to destroy ammonia and nitrogen compounds or swimmer waste. Shock treat used to mean superchlorinating to 10 parts per millions (ppm) to 20 ppm of free chlorine.
A device installed through the wall of a pool or spa that is connected to the suction line of the pump that draws water and floating debris in from the surface of the water. The skimmer basket catches large debris while the filter traps smaller particles.
A removable, slotted basket or strainer placed in the skimmer on the suction side of the pump, which is designed to trap floating debris in the water flow from the surface without causing much flow restriction.
Part of a skimmer that adjusts automatically to small changes in water level to assure a continuous flow of water to the skimmer. The weir has the appearance of a small floating “door” on the side of the skimmer that faces the water over which water flows on its way to the skimmer.
A fast-dissolving, granular, stabilized organic chlorine compound providing either 56-percent or 63-percent available chlorine. Used for regular as well as superchlorination. It also contains an ingredient (cyanuric acid or stabilizer) that prevents chlorine from being destroyed by the ultraviolet (UV) rays of the sun.
Good for regular chlorination and superchlorination. It is not recommended for spas and does not contain conditioner or stabilizer to protect it from sunlight, but it is protected if stabilizer or conditioner is already in the water. It usually provides 10-percent to 12-percent available chlorine (or about 1 pound of pure chlorine per gallon); has a pH of 13; and requires that small amounts of acid be added to the pool to neutralize the high pH.
Water that has a very low calcium and magnesium content (water hardness) – usually means less than 100 parts per million (ppm) or 6 grains. Also includes water that has been processed through a water softener. Pools and spas should never be filled with soft water from a softener. Water with less than 100 ppm of hardness should be increased to a minimum of 150 ppm to 200 ppm using calcium chloride.
A family of chlorine pool sanitizers that contain conditioner (cyanuric acid or isocyanuric acid) to protect the chlorine from the degrading ultraviolet (UV) rays in sunlight. Most common types are sodium dichlor and trichlor. Granular form is dichlor which is fast dissolving and can be used for regular chlorination or superchlorination by broadcasting into the pool or spa. Tablet or stick form is trichlor which is usually used in a chlorine feeder either the floating type or the in-line erosion type used for regular chlorination only.
A discoloration or a colored deposit on the walls or bottom of a swimming pool or spa. Most often stains are metallic oxides, hydroxides, carbonates, sulfates, silicates and phosphates of such metals as iron, copper and manganese. They may appear as green, gray, brown or black.
The practice of adding an extra large dose – 5 parts per million (ppm) to 10 ppm – of chlorine to the water to destroy ammonia, nitrogen and swimmer waste which can build up in the water. This level of chlorine is required to destroy all of the combined chlorine in the water, which is called break-point chlorination.
A measure of the total amount of dissolved material in the water. It is comprised of the spent or carrier chemicals added every time chemicals are added as well as the hardness, alkalinity, chlorides, sodium, magnesium, calcium, etc. The maximum amount in a pool is 2,500 parts per million (ppm). Maximum for a spa is 1,500 over starting TDS. The only way to effectively lower TDS is to drain part or all of the water and replace it.
An apparatus or device used to monitor specific chemical residuals, levels, constituents or demands in pool or spa water. Kits usually contain reagents, vials, titrants, color comparators and other materials needed to perform tests. The most common pool and spa water tests are: pH, total alkalinity, free available chlorine, water hardness, cyanuric acid, iron and copper.
Small plastic strips with pads attached that have been impregnated with reagents that can be used to test pool water for residuals, levels, constituents or demands. The strips are usually dipped in the water and the resulting colors of the pads compared to a standard set of colors to determine concentration.
The method used to test for total alkalinity and water hardness in swimming pool and spa water. An indicator reagent is added to a sample and then another reagent (a titrant) is added until the sample changes color. The drops or amount of titrant used are equal to the concentration in parts per million.
The total amount of alkaline materials present in the water, also called the buffering capacity of the water. It is the water’s resistance to change in pH. Low total alkalinity causes metal corrosion, plaster etching and eye irritation. High total alkalinity causes scale formation, poor chlorine efficiency and eye irritation. The test measures for hydroxides, carbonates and bicarbonates.
A slow-dissolving, stabilized organic chlorine compound in tablet form that provides 90-percent available chlorine. Used for regular chlorination but must be dispensed using a floating feeder or an in-line feeder (chlorinator). Trichlor contains an ingredient (cyanuric acid or stabilizer) that prevents the chlorine from being destroyed by the ultraviolet (UV) rays of the sun. Trichlor has a pH of 2.8 and regular trichlor tabs should not be placed in the skimmer as the low pH will corrode the metal components in the equipment.
Cloudy condition of the water due to the presence of extremely fine particles in suspension that can not be trapped by the filter because they are too small. Adding a clarifier such as an organic polymer or alum will coagulate the particles and make the filter more efficient. Turbidity is measured with a Nephelometer and expressed in units of opaqueness called NTU (Nephelometer Turbidity Units).
Water that has a pH of 7.4 to 7.6, a total alkalinity of 80 parts per million (ppm) to 140 ppm, calcium hardness of 200 ppm to 400 ppm, and a TDS of less than 2,500 ppm. The water is said to be “in balance” when the water is within these parameters.
A chemical compound used to gather (coagulate or agglomerate), or to precipitate suspended particles so they may be removed by vacuuming or filtration. There are two types: inorganic salts of aluminum (alum) and other metals or water-soluble organic polyelectrolytes.