What Causes Slime to Form on a Pool Surface and pH Levels to Drop? A Texas Pool Mystery

Opucore LLC is proud to announce that Drew Stephenson, co-founder of Refresh Pool Company, has officially joined as a Nexus Member.

Drew Stephson, co-owner of Refresh Pool Company

Expert Source: Drew Stephenson co-owner of Refresh Pool Company Maintenance | Refresh Pool Company

In the Fall of 2022, Drew Stephson, owner of Refresh Pool Company, found himself in a battle against slime and low pH. The months leading up to this struggle had been unusually dry. Dry, meaning sixty-seven (67) days of a hard summer drought. Once the rains came, Drew felt relieved. Local water restrictions began to lift, and business-as-usual seemed to continue, with some nice cloud cover. Most of the time, people do the same job daily for years without change or challenge. Drew didn’t know it, but he was about to face a problem that challenged his ability to perform his pool cleaning duties for his clients.

            As the days passed, he observed a slight pH imbalance. This did not discourage him, because the pH imbalance was minimal. Drew knew rainwater had a slightly lower pH than standard pool water. With record rainfall of up to 9 inches in some areas, this decrease in pH did not surprise Drew.  Based on this knowledge, he adjusted the pool by the water-testing results, cleaned the pool, and moved on. He observed this at several pools that week and continued the same process. Over the following weeks, he began to notice a film on the water's surface at several of his pool clients’ properties, but not at all of his pool cleaning locations. While this was strange, everything was balanced, and he moved on quickly.

            The following week would turn Drew’s otherwise ordinary pool-cleaning routine into a whiplash of turmoil. As he approached one pool, he noticed a slimy film on the plaster surface. He took some water samples to check the water chemistry and noticed the pool’s pH levels were significantly low for the conditions he had observed. Again, he took the necessary steps to raise the pH levels, add chemicals as indicated by the water sampling, clean the pool’s surfaces, and move on. However, not all pools on his route were having these issues.  Throughout the week, he noticed that every single pool that had developed a strange film on the water in the weeks prior now had slimy surfaces and low pH. No matter what he did, the pools would be in the same condition on his next visit. While his clients were patient, they too were starting to want answers. Drew was their pool guy, but he had no idea what was going on and didn’t want to lie to his clients. He was just about at his wits' end when he had an epiphany. Call it God’s helping hand, keen observation, or a combination of both, but he noticed pecan trees were a common denominator at the sites with this particular problem.

            Armed with the only information he had, Drew contacted an old arborist friend. While she didn’t know the cause of his dilemma off the top of her head, she took on the challenge to help a friend. At this point, all Drew could do was put his nose down and push on. He felt better knowing he wasn’t alone in facing this challenge.

            Days later, Drew’s friend returned with a compelling theory: a massive aphid infestation was the root of his pool problems. She suspected the bugs had swarmed the nearby pecan trees to feed on their nutrient-rich sap. As the insects gorged themselves, they rained down a sticky, sugary waste product known as honeydew, which formed the initial film Drew had noticed on the water. This syrup-like honeydew, along with the sticky bodies of the aphids themselves, may have gummed up the skimmers and filter media, reducing circulation. As the aphid population peaked and the adults began to die off, their bodies fell, carrying bacteria directly into the water. With the honeydew providing an endless buffet of sugar, the bacteria thrived. They sought out the microscopic pores in the pool’s plaster to anchor themselves, secreting a defensive, slick matrix known as bioflim. This perfectly explained the greasy slime Drew had felt on the pool’s surface. Compounding the issues, the trees eventually began shedding dead leaves and other foliage in the pool water. As the leaves and organic debris decayed in the water, they may have released tannic acid, lowering the pool’s pH. When Drew asked how to fix the issues, her answer was blunt: it was environmental, and he was just going to have to ride it out.

            Trusting his friend’s advice, Drew decided to wait it out. The conditions certainly got worse before they improved, but within a few weeks, the stubborn slime faded, and the PH finally stabilized. His battle with the bizarre aftermath of the storm was over, leaving him with a humbling takeaway: just when you think you have your job completely figured out, God can always throw a curveball to teach you something new.

Disclaimer

The following blog post is provided for general informational and entertainment purposes only. By reading this story, you agree to hold Opucore LLC, its owners, employees, and affiliates harmless from any liabilities, loss, or damages—direct or indirect—arising from the use, application, or interpretation of the information and events described herein.

Please note that while this narrative is based on the genuine accounts and experiences of Drew Stephson, certain elements, conversations, and sequences have been paraphrased, condensed, or dramatized for storytelling purposes and narrative flow.

Furthermore, the environmental conditions, weather events, and biological phenomena detailed in this story accurately reflect the historical conditions documented during the specific time period described. However, this story is not intended to serve as definitive scientific fact, nor should it replace professional arboricultural, meteorological, or pool maintenance advice. Any actions taken based on the contents of this blog post are strictly at your own risk.