A short Glossary of names and terms you should know for water chemistry:

1 - Alternative Sanitizers: a group of products that sanitize pool, spa and hot tub water, by means other than the application of chemicals to the water. Includes such products as ultraviolet sanitizing systems, mineral purifiers, ionizers and ozonators.

2 - Bactericide: a chemical that kills bacteria. The most common bactericides are: chlorine, bromine, biguanide, ozone and silver. Most algaecides, other than copper, exhibit some bactericidal properties.

3 - Balanced Water: pool or spa water that is within the accepted water analysis parameters for: pH, sanitizer, total alkalinity, calcium hardness, chlorine stabilizer (chlorine pools only) and minerals. The balancing, of the pool or spa water, helps to eliminate water chemistry problems.

4 - Bather Load: You may be asked by your spa professional what the average bather load is, meaning, how many people enter the spa on a daily or weekly basis.

5 - Biguanide: the generic name for a non-chlorine, non-bromine, sanitizer that utilizes the polymer PHMB (polyhexamethylene biguanide). It is used to totally eliminate the use of chlorine or bromine.

6 - Biofilm: a slippery coating of microorganisms that can develop in poorly sanitized pools and spas.

7 - Brominator: feeding devices used to introduce bromine into pools or spas. Most automatic types can be plumbed inline. Others are simple floating varieties. All are intended to make the application of bromine easier and more consistent. Do not use chlorine in place of bromine, in any brominator.

8 - Calcium Carbonate: crystalline deposits (scale) that can form on all under water surfaces, if the water is excessively high in calcium hardness. High pH and high total alkalinity can worsen the problem. Responsible for cloudy water conditions that may result due to pool or spa water being out of balance.

9- Calcium Hardness: The measure of the amount of calcium dissolved in the water as expressed in PPM. Hard water, or water with calcium levels over 250 PPM can cause scale formation on the surface of the spa or the components of the spa.

10 - Chloramines: irritating, odorous forms of combined chlorine, formed by the reaction of chlorine with nitrogen containing waste products. Ineffective as a pool or spa sanitizer. High levels of chloramines can cause the problems of “Red Eyes” or “Stinging Eyes.” Usually requires a shock treatment to lower or destroy the combined chlorine level.

11 - Corona Discharge: a method for producing ozone, by utilizing high voltage arcing to convert oxygen (O2) into ozone (O3). Refer to the listing for Ozone for more information.

12 - Enzymes: organic agents that hasten the natural breakdown (digestion) or decomposition of oily wastes and organic residues in pools and spas.

13 - Hard Water: the term used to describe water that is high in calcium or magnesium. High levels, usually over 400 PPM, can lead to clarity and scaling problems, if not treated. Source of the calcium can be natural or can be contributed by chemicals such as calcium hypochlorite.

14 - Ionizers: equipment that sanitizes pool and spa water by providing a low level source of copper and silver ions, as the water passes over charged electrodes. Copper ions can provide algaecidal control. Silver ions can provide bactericidal control. Other types of devices (mineral purifiers) work by an erosion principle and utilize copper, silver or zinc ions

15 - Ions: the electrically charged state that an element assumes in true solution. In the ionic state, ions are chemically reactive. Some ions, such as, copper, silver and zinc, are used as sanitizers in mineral purifiers and/or ionizers.

16 - Microorganisms: This term refers to tiny, living organisms such as bacteria, protozoa, or algae.

17 - Mineral Purifier: a type of device that releases copper, silver or zinc ions into the water at very low levels. In this ionic state, these minerals can function in the sanitizer role and help control algae and bacteria in pool and spa water. Mineral Purifiers work on the principle-of erosion and do not require electrical components. Most include some type of replaceable cartridge, that contains the copper, silver or zinc materials.

18 - Organic Matter: These are carbon-derived substances typically generated by living organisms. In a spa, they are most frequently introduced into the water by bathers. Enzyme products such as Spa Perfect by Natural Chemistry are most effective at eliminating organic matter from your body of water.

19 - Oxidation: the chemical reaction by which organic matter is “burned” or destroyed, by the action of chlorine, bromine, ozone, hydrogen peroxide or non-chlorine shock. Oxidation may cause minerals such as iron, manganese and copper to form discoloring stains and precipitates, if not treated properly.

20 - Ozonator: a device for producing Ozone (O3), by either a UV (ultraviolet) light source or by electrical arcing (corona discharge). Used for oxidizing and sanitizing purposes in both pools and spas. Click here for some ordering information about Ozone Test Kits.

21 - Ozone: Ozone is a gas molecule that can be generated by an Ozonator, which is composed of three atoms of oxygen and used to oxidize the water. Ozone is very useful for regenerating bromine from bromide ions. It also acts as a supplement when used in conjunction with a sanitizer and may reduce the level of sanitizer required. You may read more about ozone later in this section of your owner’s manual.

22 - Ozone (O3): typically produced by an Ozonator installed in a pool or spa. Ozone (O3) is a form of oxygen (O2) and is a powerful oxidizing agent. It is used to destroy organic waste and byproducts and help in the control of algae and bacteria. Not a stand-alone sanitizer: needs some supplementing with chlorine, bromine or ionization.

23 - Parts per Million (PPM): The term “parts pre million” will be used frequently in the world of water care. The term simply means exactly what it says: the coexistence of any one unlike item with a larger number of “like” items.

24 - pH (potential hydrogen): The PH is used as a measurement of the active acidity, the concentration of active hydrogen molecules in the water. PH is measured on a scale from 1 to 14, the lower numbers indicating a greater concentration of active hydrogen. While 7, halfway between base and acid is neutral, the optimum level of acitity for a spa is between 7.2 and 7.8. The effects of low PH can be rapid sanitizer loss, eye and skin irritation, expedited corrosion of metals, as well as staining throughout the spa. High PH can result in cloudy water, low sanitizer efficiency, as well as eye and skin irritation.

25 - Sanitizers: Sanitizers are used to destroy bacteria and other germs in the water. Only 2 sanitizers are used in spas, chlorine (Sodium Dichlor) and Bromine (Hydrotech or Lonza). Without the use of a mineral system or an enzyme, the perferred level of sanitizer is between 2 and 3 ppm.

26 - Sequestering: This term defines the action taken to remedy high levels of metals or calcium in the water. By forming a complex that envelops materials in the water, commonly hardness ions, a sequestering chemical prevents the ions from reacting to one another, thus forming complex structures or solids.

27 - Shocking: Shocking is the act of hyper-chlorinating or hyper-oxidizing the water. This can be accomplished with a myriad of shock treatments, but is most commonly accomplished with Sodium Dichlor or Potassium Monopersulfate. The former raises the sanitizer level to at least 8 PPM, and the latter burns off chloramines or bromines. The use of P.S., or non-chlorine shock is advantageous because you can bathe only 15 minutes after treatment; however, oxidizing the water will not kill the bacteria unless there is sufficient total chlorine to free up used chlorine to actively sanitize.

28 - Soft Water: is water that is low in calcium and magnesium hard3 ness. Such water can prove to be corrosive to masonry surfaces and underwater metal parts. The calcium hardness level can be raised, to the optimum range of 150-200 PPM, by the addition of appropriate amounts of a calcium hardness increaser (calcium chloride). Vinyl pools can be maintained at a lower level: 80-200 PPM.

29 - Total Alkalinity: Total Alkalinity measures the water’s ability to resist fluxuations in the pH level. It is measured in ppm (parts per million) ranging from 0 - 400 or up. The optimum range for your spa water is between 80 and 140. This can easily be measured with 3- or 5-way test strips. With low alkalinity the pH level will be prone to dramatic fluxuations. With high alkalinity the pH becomes increasingly difficult to adjust.

30 - Total Chlorine: Total Chlorine is the sum of the free and combined chlorines in the water. Often, water will contain a higher level of total chlorine than available chlorine. If this is the case in your water, you may use a non-chlorine shock (typically potassium monopersulfate) to free up the remainder of total chlorine.

31 - Total dissolved Solids (TDS): TDS is simply the measure of the total amount of matter dissolved in the water. When this level becomes too high, action is advised.