Testing methods
There are many water test kits on the market. Electronic test kits are beneficial as they can test a wide variety of parameters including salt levels, copper, iron, and phosphates. The only issue with some of the electronic test kits can be the price. These devices can stretch the budget and are not the most cost-effective method for testing only one body of water. It is also important to keep in mind to never freeze reagents and watch the expiry dates. Yes—reagents expire.
Some test kits on the market come with everything needed: a cyanuric acid (CYA) stabilizer test for outdoor pools, Langelier Saturation Index (LSI) calculator, and a handy book on what chemicals to use and how much to use to balance water. Many pool operators will take a test sample of the water and source water to a local service company to have them test the extra parameters the kit does not include. There are also inexpensive test strips for phosphates and metallics.
However, testing water manually is the best way to stay on top of things. Regardless of how busy one is, it is important to never skip a test and just copy the last test results in the logbook. It can be a dangerous practice. Even with a reliable state-of-the-art chemical controller, electronics can fail and should never replace manual water testing.
One very important device often missing is a total dissolved solids (TDS) meter. It is crucial to know the amount of TDS in the water; this information goes a long way to having pristine balanced water. The great thing about TDS is not needing any expensive chemicals to get reduce the amount in the water. Once it reaches 2000 ppm, approximately 152 mm (6 in.) of water should be drained from the pool and then topped back up. Upon topping the water up, there is no surprise with other level changes from adding all that fresh water.
Is this water balanced?
A mentor used to ask the question: “How do you know your water is balanced?” He often received an assortment of answers. The only way to know the pool water is balanced is by using the LSI, though on many sites the LSI wheel is often found in its original packaging and had never been used.
The LSI helps keep water silky smooth and safe for all swimmers and it keeps things very simple. The LSI calculates pH, total alkalinity, calcium hardness, and temperature. Keeping TDS below 2000 ppm is also a big part of water balance. One analogy to use when training operators is to tell them to treat it like a game. The object of the game is to score zero with a range of -0.3 and +0.5. The negative side equals aggressive corrosive water, while the positive side equals scale deposits and cloudy water. The best way to keeping water balanced is to have a goal, something to aim for: 0.0 on the LSI scale.
After chemical checks and plotting results using the LSI calculator, one can see the quality of the water. If the water falls above or below zero, an operator is now more prepared to make the necessary adjustments to get the score back to zero without aimlessly adding chemicals to a pool before having all the information. Operators often say they used less chemicals than before, keeping their water always as close to zero as possible prevents the water balance fluctuations.
