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Issues & Solutions

Pool Stains Are Unsightly and Expensive to Resolve…Quick Tips on How to Avoid Them

By June 23rd, 2023No Comments

Pool stains are a huge issue for many operators. They’re ugly, make the pool water look bad, and are expensive to resolve. There are two types of pools… one that is stained, and one that is going to stain. UNLESS you follow some simple steps below:

How do stains occur? For one, metals are continually introduced with new fill water; they get more concentrated as water evaporates and new water is added. (Note: When water evaporates, pure distilled water escapes and metals stay behind, and when new water – also containing metals – is added, the overall metal content of the pool water goes up or“concentrates.”)

Additionally, bad chemistry erodes metallic equipment causing high metal levels. Common casualties are pumps and valves (leaching iron in the pool), and heaters (leaching copper).  Finally, some chemicals contain trace metals and accumulate in the pool water over time. But how does this stain the pool?  Metals stay invisible in the water while they are “in solution”.

But, they can easily “fall out of the water” when you raise the temperature, shock the pool (treating for chloramines or fecal accidents), or abruptly raise the pH (like adding bicarbonate to balance total alkalinity). Once metals fall out of the water, they commonly attach to the surface of the pool and ruin the nice white-ish pool finish.

Staining is a year-round threat but more common in pools during the winter as heaters, which are often bypassed over the warmer months are turned on and exposed to potentially corrosive water. Next, there is more evaporation of pool water, as heated water escapes faster in the cooler weather, thus all the new water helps metal levels concentrate faster. Finally, there is a lot less rain, and thus less water to dilute the metallic content of the pool water. 

What can you do to prevent stains? Here are a couple of quick tips:

Track Metals Early and Often: Few folks track their metal contents to see if they are prime for staining. Easy and accurate tests for metals are hard to find, and are both cumbersome and expensive to run. No longer. The CES SpinTouch digital tester, using the 11-test disk, provides a quick & accurate 60-sec test for copper and iron. 

Ounce of Prevention: Sequestering agents, the chemical family designed to remove metals from pool water, can be added to the pool water proactively to lessen or remove the potential to stain. The most popular among CES customers are Jack’s Magic (blue and magenta versions) and MSI (Metal & Stain Inhibitor). The Jack’s brand also comes with a test kit that allows you to measure how much you already have in the water, and so you only add what is needed. The problem is that the treatment doses are so small that some folks just plain forget to treat the pool, and they stain. One of the best ways to overcome this is to add an inexpensive automatic feed station that is programmed to feed the correct ounces per week, and then order our sequestering agents in 5-gal pails, replacing pails when they are empty.

Keep Your Balance: Some companies just concentrate on controlling chlorine and pH, and they’re missing the boat. Proper water balance also includes maintaining proper calcium hardness and total alkalinity, and keeping your total dissolved solids within reason. If those three are ignored, the pool water will quickly turn aggressive and will start the 24/7 process of eroding your pool equipment and pool surfaces, making the pool much more likely to stain. 

Double Duty: Those customers utilizing CES’s Pulsar Treatment programs get several side benefits. First, the water stays chemically balanced (in terms of calcium and alkalinity or saturation index), as a byproduct of the chlorination, so there is less corrosion of pool components. Also, the Pulsar briquettes contain a special stain inhibitor in every tablet, so it helps keep metals at bay. Finally, we see excess metals sometimes collecting in the feeder, but it’s better than showing up as a stain in the pool. This is one reason why Pulsar pools don’t stain as often, and the chemical is known as an All-in-One solution.

All in all…Early Detection & Proactive Treatment can make stains a thing of the past. Please let us know how CES can assist you in keeping your pool clean and inviting, and keeping your pumps and heater happy where they are, instead of being plastered on the pool floors and walls.