Identifying, testing and treating surface stains
Identifying and correcting unsightly pool surface stains is important for more than just aesthetics; it can also save water features, plumbing and more.
“The stain itself might be the result of a much larger issue,” says Joey Chavez, interior surface specialist for POOLCORP.
Chavez says copper staining, for example, can indicate copper being stripped from equipment, water features or even old pool plumbing.
“It could even be from a simple algaecide, but once [copper is] stripped from equipment, it’s gone and those pieces of equipment are not cheap to replace,” he warns.
Chris Marcano, executive director of the National Plasterers Council, says misidentifying a stain can lead to improper treatment, which may worsen the problem or cause further damage.
“Using an acid wash on an organic stain won’t be effective and might unnecessarily erode the plaster surface,” Marcano says. “Proper identification allows pool professionals to address the root cause of the stain, ensuring comprehensive and lasting solutions.”
Marcano adds that certain types of stains can also indicate underlying water chemistry issues that, if left unaddressed, can lead to more serious problems such as corrosion or scaling. Pool pros who take a proactive approach can help reduce long-term maintenance costs.
Assessing the color, location and circumstances in which the stain appeared is key, and corrections typically involve a combination of chemical treatments and mechanical cleaning, Marcano says. He emphasizes the importance of maintaining proper water chemistry to prevent future staining, including keeping the pH, alkalinity and calcium hardness within recommended levels, plus regularly checking for metal content in the water.
Chavez recommends using stain identifier kits instead of products like muriatic acid, especially when working in front of a customer. He warns that customers may take a DIY approach to save time or money which can lead to other challenges.
“Muriatic acid can be seen as some sort of home remedy,” Chavez says.
A product like muriatic acid may remove or identify a stain, but it may not always be what is needed to solve the issue.
Nadia Beane, chief operating officer for Jack’s Magic, a company that makes pool stain identifier kits and products, encourages anyone looking to identify surface staining to use a kit instead of diagnosing a stain based on color.
“While [you can] diagnose based on color, there are a lot of surface stains that look similar but have different methods of removal,” Beane says.
Beane, Chavez and Marcano agree that kits help take out the guesswork and ensure a more targeted approach to removal.
Chavez notes that pool pros should also know how to use a kit before arriving at a service call.
“The key is practice,” he says. “If you pick up a kit on the way to look at a pool and you’ve never used it, it’s going to show while you’re fumbling with it poolside, which can be key to the customer believing the results or not.”
Stain kits include a small variety of treatment chemicals that are placed on the stain — essentially microdoses of the treatment product that will eventually be used to treat the whole pool, says Kevin Vlietstra, technical director and regulatory specialist at Haviland Pool & Spa Products, makers of Stain Drop Stain Removal Verification Kit.
He says the first step when arriving at a pool is to lay out the contents of the stain kit, then apply the chemicals in the kit to the problem area of the pool, ideally where the stain is most intense.
“When a stain is close to the surface, you can place the treatment product directly on the surface because the chemistries won’t immediately dissolve before it reaches the stain on the surface bottom,” Vlietstra says. “However, since not all stains are close to the surface, these kits come with multiple single-use dosing pouches that can be filled with the treatment product and tossed into deeper areas of the pool — usually with the help of your telescoping pole to maneuver the pouch to the ideal spot — where it then starts working to lift the stain.”
Ideally, the stain would be completely removed, but several factors, such as the intensity and age of the stain, might only result in a slight improvement. Vlietstra explains that stain treatments often work in stages, requiring an initial treatment to be applied first, which then enables a subsequent treatment to lift the stain more effectively.
“Technicians often expect a total removal of the stain, but the kit is used to identify the stain, not remove the stain,” he says. “Once all the treatment products in the kit have been used, determine which chemistries lifted the stain the best.”
Along with using stain ID kits, Beane advises documenting as much information and history about a pool as possible.
“You’re essentially a detective piecing together a mystery,” she says. “Basic questions like the kind of equipment and regular chemicals used are invaluable towards helping determine what a stain is and how to remove it.”
Beane also recommends taking note of other context clues when you’re in a customer’s backyard like landscaping, pets, staining present on nearby buildings and whether or not customers have green-tinted hair after being in the pool.
“All these can help you identify potential causes for any issues you see and prevent them from reoccurring,” Beane says.
In addition to stain ID and removal products, Jack’s Magic offers a certified stain specialist program for pool pros. It’s designed to familiarize pros with the types of stains, scaling and discolorations they may see in the field. Beane says stain removal can be daunting, so it’s a service that can set professionals apart from others.
“By providing this specific education, we’re able to help pool pros increase their recognition of problems and their potential solutions,” Beane says. “This helps professionals better judge whether those are situations they want to get involved in and if so, how much to charge for their service.”
Chavez discourages relying on social media for training and says to pursue legitimate sources of information like Jack’s Magic certified program and educational materials provided by the National Plasterers Council and The Pool Chemistry Training Institute. He also advises attending local pool shows to learn from the professional instructors there.
Marcano agrees that specialized training and knowledge in stain identification and correction can differentiate pool professionals in a competitive market.
“Customers appreciate working with experts who can diagnose and solve problems efficiently, ensuring their pools remain in pristine condition,” he says. “This expertise not only enhances customer satisfaction but also builds trust and loyalty.”
