WATER CHEMISTRY

Water is water, isn’t it? If I can drink the water, why can’t I swim or soak in it? These are good questions, but the answers may not be simple. As you remember from chemistry in school, all water starts as H20. But what happens after that is why all water is not the same. If the water comes from a well, there are usually minerals and metals dissolved in the water because of underground conditions. If the water comes from a municipal source, there may be chlorine, fluoride, phosphates, and other compounds added to the water.

Water that comes from your tap may be safe to drink, but it is probably not safe to swim or soak in. When you fill the pool or tub, the water probably has minimum levels of bacteria, germs, or algae present. However, exposing that water to the air, sunlight, and to bathers, causes great changes to take place in the water. Thankfully, most changes are manageable so the water is safe to use.

WATER BALANCE

Water Balance is a term used to describe the condition of the water when all the factors such as pH, total alkalinity, calcium hardness, total dissolved solids, copper, iron, and manganese along with temperature of the water are in their proper relationship. Water Balance is measured by a formula called Langlier’s Index. The ideal index reading is 0. A significant plus reading will cause scaling and cloudy water. A significant minus reading will cause etching, wrinkles in liners, and “red eye” in bathers.

pH

The term pH is a chemical symbol measuring the potential of hydrogen expressing the acid to base ratio of the water in the pool. The pH scale reads from 0 to14 with midpoint of 7 being neutral (neither acidic or caustic). What new owners have trouble remembering is that this scale is logarithmic and not numerical. This means when you move from the neutral 7 up to the reading of 8, you have not increased the amount of caustic in the water one time, but multiple times!

TOTAL ALKALINITY

Total alkalinity is the measurement of the carbonate, bicarbonate, and certain other alkaline (caustic) chemicals in the water. The desired range is between 80 and 150 ppm. A low total alkalinity reading increases the sensitivity of pH changes in the water. This will allow the pH to “bounce” up and down. This is not good for the pool or the equipment. If the total alkalinity is high, the water will be cloudy and will use a lot more of the sanitizer.

CALCIUM HARDNESS

Calcium Hardness is the measure of the combined calcium ions present in the pool water. The ideal range is 200 to 300 ppm. A low calcium hardness concentration will cause the water to be a pale clear green and in the case of a plastered pool the water will actually attack the plaster. A high calcium hardness concentration will cause cloudy water and a very high concentration will cause the water to be a milky white.

STABILIZER

Stabilizer is a white powder called Cyanuric Acid. Stabilizer does not help in disinfecting or algae kill, but in the right concentration stabilizer greatly aids in reducing the chlorine demand of the water. Bright sunlight can draw the chlorine concentration out of a pool within a matter of a few hours. You could have the correct chlorine reading in the morning and a green pool in the afternoon if the correct amount of stabilizer is not in the water – 30 to 40 ppm range.

CHLORINE

Chlorine comes in all types, concentrations, and container sizes. The effective sanitizer is the hydrochlorous ion that is part of the molecule of the different chlorine sanitizers. Chlorine is a mix of organic or inorganic compounds and varies from a concentration of 5% such as NaOHCl2 (bleach) to 99% C3N3O3Cl3 (Trichloro-S-Triazinetrione). Not only does chlorine vary in “strength” but different chlorine compounds dissolve at different rates, have different pH values, and most importantly, have different uses. There is a section listing the different chemical formulas for sanitizers and their properties and uses found in either of the Owner’s Guides accessed through the Site Map.

Treat all chemicals with utmost care and follow the label instructions exactly! NEVER PUT ANY TYPE OF NON-STABILIZED OR POWDERED CHLORINE IN A FEEDER! IT MAY EXPLODE WHEN MIXED WITH WATER!

WATER CLARITY

Most new owners start out okay, but then things go wrong! There are so many things to remember and so many variables such as weather, wind, bather load, etc. Many people other than just a new owner become confused and end up with the “swamp” look. It is better to understand what is going on and what you can do to prevent “swamp” water than to spend your time and money trying to clear the “swamp.”

Every owner experiences cloudy or green water sooner or later. This is a given fact. The question is always, “What did I do wrong?” You may have done nothing wrong, but you failed to do some additional step that would have prevented the cloudy water.

First let us say that each pool or tub is unique. We can only talk in general terms and you should feel free to bring your pint of water to our lab at any time. Cloudy water usually happens when there has been a change in the weather such as a rainstorm, after a party, or after you have followed the same routine for an extended period of time. Yes, doing the same thing over and over can lead to trouble given enough time.

Two things prevent cloudy water: 1- Chemicals in the correct dosages, 2- Proper filtration. Saving money by not shocking the pool or tub after a rain, or a party will actually cost you more when you have to clean up the “swamp.” With a swimming pool, if you don’t run the pump for twenty-four hours after a rain, party, or shock treatment, you will almost guarantee cloudy water.

So you see, it is not really something you did wrong. It is what you did not do. You do not shorten the life of the pump by allowing it to run twenty-four hours per day. If the filter does not have a chance to do its job of removing the dirt from the water, no amount of chemicals will keep the pool clean and inviting forever. In the summer, you probably need to run the pump and filter a minimum of twelve hours a day. At the first sign of any changes in the water, you must run the pump and filter all the time – twenty-four hours per day!

Trying to save money by not using the correct dosages of chemicals or running the pump is foolish! You will certainly spend more money cleaning up the resulting “swamp” than you saved by not staying on top of the changing demands of the water.