Puzzle Me This

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When homeowners buy backyard pools, what they're really buying is water; and not dull, cloudy water, but clear, sparkling water that pleads for a swim. That's what the customers pay for.

Unfortunately, it's not uncommon for pool owners to complain that their water lacks the transparency it once had. They've tried everything, they say — a bottle of this, a jug of that — but nothing seems to work. Often these flailing attempts only make the situation worse.

The fact is, pool chemistry and problem solving are tough subjects to master: Certainly the homeowner, and even full-time industry professionals, can benefit from a refresher now and then.

Therefore, in the interest of clarity — of both pool water and counsel — we offer this brief guide to help diagnose and treat those cloudy water culprits.

Part I: Cloudy Water

PROBLEM: Poor Filtration This is the first thing to check when a homeowner complains that his or her pool has suddenly become cloudy. If the filter system isn't working properly, disinfectants, clarifiers and algaecides can't do their jobs. Every product created for pool health depends on proper filtration.

SOLUTION: Check the pool for dead spots that indicate improper circulation. There's no way a filter can clean out debris that never passes through it.

Water level could also be at the root of the problem if it is below the skimmer and the skimmer can't grab drifting debris.

Less-obvious filtration problems include improper filter size for the pool volume and incorrect flow rate for the pump. Clogs can also build up in plumbing lines, and filter media may be showing signs of wear and tear or channeling in a sand filter. If scale or buildup is present on the filter, it may be clogged with oil and dirt.

If necessary, adjust the return line, change or clean the filter media, and check manufacturers' guidelines to make sure filter sizing and pump flow rate are correct.

PROBLEM: High TDS High total dissolved solids can especially be a problem for homeowners who do not drain their pools annually. TDS is, as the name suggests, the sum of all dissolved solids in the pool, including calcium carbonate, swimmer waste, dissolved organic and inorganic matter and salts from chlorine residue.

Ideally, the TDS level should be between 1,000 and 1,500 ppm. Levels above 1,500 ppm can reduce chlorine efficiency up to 50 percent, leading not only to unclear water, but a health hazard as well. One symptom typical of high TDS is the water will taste salty because of its high mineral content.

SOLUTION: Dilution by draining and refilling is the only way to deal with high TDS. But you can encourage a pool owner to prevent high levels of TDS by using a clarifier weekly to aid in removal of accumulated material to the filter.

PROBLEM: Chloramines A heavy chlorine odor is the telltale sign that chloramines are present in a pool. Most owners use chlorine as a sanitizer, but don't realize that chlorine combines with ammonia and nitrogenbased organics from swimmer waste to form chloramines, or combined available chlorine, which can do more than take the sparkle from their pool. Chloramines can also cause swimmers' eyes to burn and reduce a sanitizer's ability to eliminate diseasecausing bacteria.

When the amount of combined available chlorine is higher than the free available chlorine — the chlorine that is working to sanitize your pool — the pool water becomes cloudy and unsafe for swimming.

SOLUTION: The pool needs to be shocked to remove the combined available chlorine. Adding chlorine up to 10 times the level of combined chlorine in the water, known as "breakpoint chlorination," will completely eradicate those irritating chloramines, and their evil smell with them.

Keep the pump on while shocking the pool, and it's a good idea to do it at night to keep the sun's UV rays from destroying some of the concentrated chlorine and hampering the effect of the shock.

A chlorine-free shock that contains potassium monopersulfate (MPS) may also be used to oxidize waste. MPS contains oxygen to clean up the waste and chloramines. After clearing up the water, a chlorine-free shock and chlorine can work efficiently together.

Regular clarifier use can also help prevent chloramines in the future.

PROBLEM: Organic Waste Homeowners are often their own biggest impediment to water clarity. Many don't realize that when they enter the pool the water absorbs their dirt, perspiration, perfumes, hair products, oils, sunscreens and millions of bacteria.

Weather can also compromise transparency and quality of pool water. Wind can blow leaves and grass clippings into the pool, rain can drain silt and organic material from the atmosphere into the pool, and acid rain can cause metal ions to precipitate. Even sunny days can do damage — UV rays compromise even stabilized chlorine, and evaporation can mean a buildup of dissolved solids and salts.

SOLUTION: Contaminants from all of these external sources can be reduced with a little diligence and creativity.

Pool owners should be encouraged to take a firm line on the personal hygiene of bathers. Even a quick rinse at an outdoor shower can help.

In addition, covering the pool from the elements prevents an enormous amount of contamination and saves chemicals. For instance, a simple windbreak made of semi-permeable fabric attached to a chain-link fence can dramatically reduce the amount of debris blowing into the pool, and an automatic pool cover can attenuate the influx of pollutants and radiation when the pool is not in use. Also make sure proper levels of cyanuric acid are present in the water to reduce loss of chlorine due to exposure to the sun.

Failing these measures, the pool's normal defense systems require extra vigilance under such assault. Filter maintenance and water testing must become a ritual.

If oily contaminants are suspected, use a natural, non-oil-based clarifier. Most clarifiers are petroleum based, which won't help clear up oil in a homeowner's pool and could cause more problems by clogging filters and creating scum on the waterline.

PROBLEM: High TA Total alkalinity is the sum total of all alkaline substances in the water. High total alkalinity (above 120 ppm) can cause calcium carbonate to precipitate out of pool water, making it cloudy.

On the other hand, when alkalinity is too low (below 80 ppm), water balance becomes extremely precarious, and customers can become quite anxious as their pH readings begin to fluctuate wildly. It's a discouraging situation for pool owners who don't understand the relationship between total alkalinity and pH.

SOLUTION: You might want to explain to homeowners how the two work together. Some like to think of total alkalinity as the father and pH the teenage son of pool water balance. Total alkalinity in the proper range will help keep pH in line by giving it the ability to resist external influences. Adding an acid such as muriatic acid or sodium bifsulfate will lower total alkalinity. Thirteen ounces of muriatic acid will lower total alkalinity by 10 ppm in 10,000 gallons of pool water.

If total alkalinity is too low, a product containing sodium bicarbonate should be added according to the manufacturer's guidelines to bring total alkalinity back in range.

Keep in mind the ideal level of total alkalinity depends on the type of chlorine being used. If the main chlorine source is liquid sodium hypochlorite, which is alkaline, the total alkalinity should be maintained in the lower range of 80 to 100 ppm. If a stabilized, acid-based chlorine such as trichlor is being used, maintain the total alkalinity in the 100 to 120 ppm range.

PROBLEM: High Phosphates Phosphates can exist in both natural and manufactured sources. Some forms occur naturally in rivers, oceans, rock, leaves and bark. Manufactured sources include fertilizers, soaps, detergents, shampoos, sodas, food — and pool chemicals.

Phosphates can pose a problem by causing cloudy water and slimy walls and floors, but they also are an essential food source for plants, including algae.

Orthophosphate is the main form to worry about. And pool chemicals containing trisodium phosphate (TSP) can convert harmless polyphosphate to orthophosphate. High orthophosphate levels also interfere with the chlorine generator's ability to produce hypochlorous acid, the killing agent of chlorine.

SOLUTION: Add a phosphate remover to the homeowner's maintenance program. Also encourage owners to use a natural clarifier that will flush the pool of phosphates and debris containing phosphates.

Testing for phosphate levels should become a normal part of the opening, closing and maintenance procedure for all pools.

Part II: Ugly Water And Algae

PROBLEM: High Metal Content Sometimes customers aren't even aware of discolored water until they see stains on pool surfaces, filters or even swimsuits. Unlike cloudy water, which is easily spotted, discolored water often remains transparent with a nearly undetectable green or brown tint.

Discolored-but-still-clear water is typically caused by metal ions precipitating out of the pool water. The most common metals found in pool water include iron, copper and manganese. They can come from ground water or municipal water.

When homeowners complain that their hair or swimsuits are turning green, remind them that the problem isn't a reaction to chlorine, but rather excess copper ions. Copper and other metals will often precipitate out of pool water when the pH is too low. Other symptoms of a low pH include corrosion of metal pipes or the heat exchanger if the pool has a heater, and these can be a source of dissolved metal as well.

SOLUTION: If you've got metals, apply a sequestering agent (also known as a chelating agent) according to the manufacturer's guidelines. It will hold the metals in solution so they can be removed at the filter. Of course, this can only happen if the filter is in good working condition — clean, unchanneled (if sand), and working at the proper pressure differential.

Keep in mind that your sequestering or chelating agent works better if your pool water is properly balanced for pH, alkalinity and hardness. If necessary, raise the pH with sodium carbonate (soda ash), which is a base. In spas, use sodium bicarbonate. Particularly where metals are known to be present in the local water, sequestering agents should be part of the pool maintenance regimen. Sequestering products should be considered a low-cost insurance policy against a very high-cost mishap — a stained pool surface.

PROBLEM: Algae As opposed to the slight water tint indicative of metals, homeowners will definitely notice if their pools become the hydroponic homes of green, yellow or black algae. They will likely panic and rely on your expertise to solve the problem.

When pool water turns yellow, green or develops black stains at the wall, algae is the likely cause. Some algae are free-floating and others grow on pool surfaces, making them slimy. Pool owners hate algae in their pools; they are embarrassed to have guests over and confused about how to deal with it.

Some of the factors that encourage algae growth include a lack of sanitizer, water temperature over 80 degrees, poor circulation, high iron content and high phosphate content. Often when customers go away for vacation and solar bubble covers are left on for extended periods, the water beneath heats up rapidly. At the same time, chlorine residuals decrease, and the combination creates an environment where algae will thrive.

SOLUTION: Chlorine is the most common agent used to fight algae. It will kill algae and then act as an oxidizer to destroy waste material. But algae move in where the sanitizer has failed.

Use a broad-spectrum algaecide, well circulated throughout the pool, to kill most strains of algae. Make sure to put all the poles, nets, other cleaning equipment and pool toys into the pool when you treat it, and then clean the filter. Otherwise, algae can be reintroduced to the pool later.

Black algae that have a good firm grip on the sides of a gunite pool will have to be scrubbed repeatedly with a stainless-steel brush. When covering a large area, this becomes a good program to develop the triceps and deltoid muscles. Once brushing has opened the algae cells, an algaecide or even a chlorine product such as trichlor can get inside and kill it.

Using an algaecide with a long-lasting residual can help prevent further outbreaks, which are all too common with algae infestation. The residual is important because when algae die they release phosphates that will feed any lingering or reintroduced algae, causing the problem to come back again and again.

There's no reason not to use a broad-spectrum algaecide as part of the owner's routine pool maintenance. It's a backup. If for some reason, due to poor circulation or neglect, the sanitizer fails, the algaecide is there to prevent a big blooming problem.

Consumer Confidence

Pool owners rely on professionals for education and expertise — particularly when the pressure is on due to a water problem that has shut down the pool. Such a situation is the opportunity for a dealer or service company to win a customer's confidence forever.

When customers are tempted to start throwing bottles of chemicals at a cloudy pool, clear answers will keep the situation manageable.

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