Swim Hard, Sanitize Harder
Maintaining healthy water chemistry in high-use residential pools
While commercial pools are built for constant traffic, heavily used residential pools face different challenges. Higher bather loads quickly change water chemistry, leaving service pros and homeowners scrambling to keep water safe, clear and balanced.
How bathers impact water chemistry
Alicia Stephens, director of training and education for BioLab Inc. in Lawrenceville, Georgia, says higher bather loads significantly affect sanitization, pH levels and alkalinity.
“Bathers change water chemistry in a lot of different ways,” Stephens says. “And bather waste is some of the toughest stuff to break down.”
From lotions and perfumes to sweat and body oils, everything swimmers bring with them affects water chemistry. The Centers for Disease Control and Prevention emphasizes that disinfectant and pH are the first line of defense against germs — and recommends more frequent testing when pools are used heavily.
Preparing for parties and heavy use
Sanitizer residual is eaten up quickly with a higher bather load, and Stephens recommends being prepared for extra treatments.
“A good rule of thumb is, if you’re having a pool party, treat before it and after it,” Stephens says. “Prepare for it. It’s OK to bump your chlorine level up to what you would consider to be higher than normal before you have the pool party.”
Weekly service may not suffice. Stephens suggests increasing treatment frequency for any pool that’s used more than average.
Why weekly service isn’t enough
Matthew Harvey, CEO of LWR Pool Care in Bradenton, Florida, has seen just how quickly high-use residential pools can shift out of balance.
“As a large, southwest Florida-based service company, we see firsthand just how affected a pool can be less than 24 hours after our visit,” Harvey says. “With six days to go until our next visit, it is near impossible to balance or maintain LSI levels.”
That’s why Harvey advocates for twice-weekly service as a new industry minimum for residential accounts with heavy use.
Common misconceptions about chlorine
Murky water is the most obvious indicator something’s off, but Stephens and Harvey say misconceptions make things worse.
Some homeowners believe more chlorine is always better, running their systems at 100% all week. The result? “They’ll leave them there for an entire week and then wonder why CH is over 10ppm with a pH level in excess of 8,” Harvey says.
Another myth: A strong chlorine smell means the pool is clean. In reality, it signals the opposite.
“If you’re smelling chlorine in your pool, you don’t have enough, and what you do have is the wrong kind,” Stephens explains. “That’s never what you want to smell.”
The strong odor means there isn’t enough free available chlorine in the pool, and the chlorine becomes inactive when chlorine molecules bond with nitrogen molecules, creating chloramine. Chloramines are ineffective for sanitizing and signal that the pool should be shocked or treated.
Tools, training and communication
Harvey stresses the value of visuals when educating clients.
“Photos don’t lie,” Harvey says. “We have shown clients before-and-after [photos of] filters with heavy sun lotion usage, and that has often been an effective way to portray just how damaging the lotions and oils can be to the pool’s health.”
On the equipment side, Stephens points to circulation and filtration upgrades as key tools for managing high-use pools. Variable-speed pumps, she says, can be “game changers,” allowing more frequent circulation to handle the extra contaminants.
“You will improve your odds and have a better-looking pool that’s easier to take care of because you’re getting better circulation between more garbage and waste,” Stephens says. “It’s not that you need different circulation or different filtration, you just need more of it.”
High-use residential pools may not be commercial facilities, but they can demand commercial-level attention. With more frequent treatments, better communication and upgraded circulation, service pros can help homeowners enjoy their pools safely — even at peak use.
