Feature Article - April 2018
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Expanding Pools of Knowledge

Control Maintenance Costs Without Sacrificing Safety

By Rick Dandes

Surface corrosion: Rust on stainless-steel elements may be associated with corrosive properties of water or from chemicals in the air that may attach to the metal and accelerate corrosion, DeRosa said.

Eye burn: Eye burn is often a result of elevated combined chlorine (chloramine) levels. Combined chlorine can result from insufficient free chlorine levels to support oxidation of organic matter, including urine and sweat from swimmers.

Swimmer cough: When swimmers routinely complain of difficulty breathing or coughing during their workouts, DeRosa said, "this can be attributed in part to poor air handling. It may be necessary to examine how off-gassed chemicals are removed from the surface of the water. Gentle ceiling-mount fan systems may help move air to the sides of the pool where it can be exhausted through the building's air handling system or similar gutter or deck-based system designed to exhaust pool air from the surface of the water.

Turbidity: Pool water should be clear, DeRosa said. When the surface is not disrupted by swimmers, it should be easy to see the bottom outlet or a marker tile on the bottom of the deepest section of the pool from a distance of no more than 10 yards. Haziness is the first indicator that water clarity is compromised, whether by inadequate sanitizer levels, elevated pH levels, or unbalanced water. Take corrective action immediately to prevent water from becoming cloudy. Turbid pool water is a major safety concern. The entire pool should be closed whenever a portion of the pool water becomes cloudy. The pool should not be reopened until the cloudiness has been resolved and chemicals are within acceptable ranges.

One of the primary causes of cloudy pool water is due to an overload of swimmers in a short period. Clean as we may think we are, the human body carries many contaminants.

There are hundreds of reasons for a pool to go cloudy, explained Terry Arko, a Certified Pool Operator and Instructor and a water specialist, with a Norwalk, Conn., company specializing in products for aquatic facilities. "The cause could be anything from improper water balance to an undersized filter," Arko said. "Surprisingly, many aquatic facility managers immediately treat a cloudy pool with chemicals to clear the water. Many times, it is assumed that the cloudiness in a pool is from a lack of chlorine sanitizer. In response, an aquatic facility manager may throw a chlorine shock in to clear up the pool. However, sometimes the pool does not clear. Next, they will try a clarifier. Again, the pool does not clear. Many chemicals are tried but to no avail. The pool remains cloudy. What is the answer?"

Arko suggested the cloudiness might not be a chemical problem but rather a physical problem. "Most likely, it is a filter problem," he said. "Therefore, when a pool goes cloudy the first thing to check before adding chemicals is the filter. It should be clean. Check the flow rate and make sure the filter is the proper size."

Arko advised taking other steps, including:

  • Checking the pump strainer and impeller.
  • Checking the system for air leaks and clogs.
  • Super-chlorinate or oxidize.
  • Add a chitosan-based clarifer immediately after shocking.

If the filter and pump are working properly but the pool stays cloudy, it is then time for chemical treatment, Arko said. "First, shock oxidize the pool to break up and reduce organic particulate material that is present. One of the primary causes of cloudy pool water is due to an overload of swimmers in a short period. Clean as we may think we are, the human body carries many contaminants, such as bacteria and organisms from our skin, hair and saliva. An active swimmer can release up to two pints of perspiration per hour that contains hundreds of different organic contaminants. This does not include the lotions, deodorants, hair care items and soaps on our skin that are released into the pool water. Summer storms that bring heavy rain or wind can also introduce debris and contaminants."

Oxidation can be accomplished by super-chlorination or using a non-chlorine oxidizer, Arko said. "While oxidation is effective, it can still leave behind remnants of organic contamination that now will be too small for the filter to catch, and this could lead to lingering cloudiness. The answer now would be to add a clarifier. A clarifier is a long chain polymer molecule that works by introducing positive charges into the pool water. Most particulate material that is in suspension in pool water has a strong negative charge. This small micron negative material is attracted to the large positive molecules of the clarifier. The material becomes filterable and is easily removed."