By Claudio Azurmendi
A green pool, a runny nose, and a car that will not start would generally not be mentioned in the same sentence let alone the same paragraph; however, each event indicates the presence of a problem. For instance, with the car, the battery may be dead or the starter may need to be replaced. A runny nose could be the sign of a nasty cold coming on or an allergy, and a green pool signifies the presence of copper or algae. Practical experience teaches one to either address problems as they arise or try to prevent them from happening altogether through diagnostics and maintenance. For instance, a vehicle owner ensures a clean start when they turn the key by taking their car in for inspection and performing routine maintenance, while going to the doctor for regular physicals can reveal problems that would have otherwise gone undetected until a major illness occurs. Therefore, regular trips to the car care professional and family physician can not only help to prevent minor annoyances, but also help to avert catastrophic events like major engine failure or a heart attack. The question then becomes: Is it more expensive to take the car to the shop periodically for diagnostics, or to replace an engine, and which is going to be more time consuming? Preventative maintenance and testing is the answer as it will be less costly and time consuming no matter which of the three scenarios are presented. In fact, the pool owner or operator who tests their water routinely will get the preventative care necessary to achieve the most enjoyment out of their pool and avoid costly treatment and damage to pool equipment and surfaces.
The truth about water discomfort
Swimming pool and spa/hot tub owners periodically complain about burning eyes, irritated skin, or strong chlorine odours. Irritated skin does not fall under the category of costly treatment; however, nobody wants to swim in a pool that makes their eyes burn. Many assume sanitizers contribute to these recreational water maladies when in fact these problems occur when pool owners treat, or undertreat, in many cases, without any idea where the pH, free chlorine, or combined chlorine levels lie. By doing this, they potentially subject themselves to discomfort caused by various chemical extremes.
The truth about discomfort and noxious smells often surprises bathers. Insufficient chlorine leads to the buildup of chloramines, which cause offensive odours and bathers’ eyes to sting. Testing pool water that has a strong chlorine odour may, in fact, reveal a lack of chlorine instead of excess sanitizer. Therefore, taking a water sample to a pool professional for testing is a necessary step towards a clear, enjoyable pool or spa experience without the irritation. For example, indoor pools at family recreation centres are notorious for the obnoxious chemical smells they inflict upon patrons. Bathers seem to tolerate the smell because they assume the water is over chlorinated and, therefore, feel protected; however, facility staff may discover after taking a water sample in for testing that the water has a combined chlorine residual of more than five parts per million (ppm). As a result, they shock the pool water accordingly and restore the water to a comfortable bathing status. Patrons who attend recreation centres, which do not perform regular water tests, will continue to suffer. Combined chlorine is not an effective sanitizer, and it prevents free chlorine from doing its job. So, not only is water sanitation compromised, but it is uncomfortable for bathers as well. With routine water tests, combined chlorine levels can be determined and an accurate assessment for treatment and maintenance can be made. Further, depending on the bather loads and weather, some weeks may require more chlorine than others; therefore, water tests play a vital role in determining when the maintenance sanitizer and shock is not sufficient in keeping a pool safe for swimming, let alone less irritating. When examining chlorine and combined chlorine only, regular water testing will catch problems caused by insufficient product additions. If pool owners fail to routinely test their pH, instead of not adding enough, they may be adding the wrong product. For instance, a pool with a pH level of eight and total alkalinity (TA) level of 125 ppm would not need sodium bicarbonate for balancing. However, pool owners who shock their pool once a week and add sodium bicarbonate periodically without testing the water first do not know whether or not their pH is high or low. If bathers were experiencing burning eyes, adding sodium bicarbonate could possibly exacerbate the problem rather than making it better. By determining the pH and ensuring the appropriate product is added to the pool, regular water testing helps eliminate bather eye and skin discomfort.
Defending against cloudy water
The health of the filtration and circulation system—along with proper water chemistry—determines whether or not pool water will turn cloudy. Phenol red or a total alkalinity titration may not be able to explicitly indicate the existence of a filtration problem; however, regular water testing can rule out water balance and chemistry issues, leaving a filtration or circulation problem as the only possible culprit.
The process of elimination when looking for the cause of cloudy pool water should start by testing pH, total alkalinity, and calcium hardness. Under the right conditions, high pH forces calcium carbonate out of solution. Once this occurs, suspended particles accumulate leading to haziness and cloudiness. Testing pH, total alkalinity and calcium hardness allow for appropriate pH decreaser or scale inhibitor recommendations that prevent cloudy water before it even occurs. If the water is tested and chemical balance is not the root cause of cloudy water, the pump and filter can be inspected for malfunction. Without the information provided by regular water testing, pool owners are at risk of running into a chlorine demand situation, or they may already be experiencing this problem without knowing it. Chlorine demand indicates the inability of pool water to maintain a free chlorine residual. This phenomenon leaves bathers unprotected as any free chlorine added to the pool is immediately extinguished before bacteria and viruses can be killed. Not only does free chlorine protect bathers from bacteria and disease, it also oxidizes material in the water to facilitate filtration, which keeps the water clear. Pool owners and operators who do not test the water for free chlorine run the risk of developing a chlorine demand situation, which is often coupled with cloudy water.