In April's Feedback, we ran a letter from Charlie Reatherford, who wrote looking for information on dealing with scale on marble-dusted pools. Two readers responded. — eds.
Dear Charlie,
Sorry we missed you at the Western Pool & Spa Show, in Long Beach, Calif. We taught a class on this very problem. If it is scale that has built up on the walls over the winter we recommend turning off the equipment and adding one gallon of muriatic acid per 1,000 gallons of water on old pools, or one gallon per 2,000 gallons of water on plaster less than a year old. Brush the pool after you add the acid to mix it up, then check the plaster every three days by rubbing the wall with your hand until the calcium has dissolved and the wall is smooth. At this point we put a pump in the pool and drain this acid solution into the sewer system, not the street gutter. The pool gets a very light acid wash and you're done!
You will notice I did not mention sanding. Power sanding usually leaves a salt-and-pepper look to the plaster; we sand benches and steps with 80-grit wet and dry sandpaper applied by hand.
Bob FowlerFowler's Pool ServiceSan Diego
Dear Charlie,
During the closing process add a scale inhibitor. N. Jonas has a wonderful winter kit that we sell to our customers. It has Scale Inhibitor, Winter Algaecide, and an enzyme floater. The Mesh Winter kit has an added bottle of phosphate remover. They are great, and we have been selling them for over 20 years and have had no complaints about scaling. There have been a few customers that skipped this step and wished they had not.
When the scale is already present, you can use a product called "Hydro Quest" if you can still find it. One of my distributors down here found a bunch last year and I do believe they still have some. A 1-pound bag (good for 12,000 gallons) is dissolved into a pail of hot water, poured into the skimmer, and circulated at least 24 hours non-stop. You need to brush the pool every day twice a day. The scale usually will go away in about two weeks or less.
The scale buildup can be prevented throughout the year also by keeping scale inhibitors in the water. Jack's Magic makes a sequestering test kit that lets you measure the amount that is in the water so you know when you need more. Speaking of Jack's Magic they make several scale inhibitors that work with different chemical systems. Most every chemical company makes a scale inhibitor, sequestering agent, or chelating agent. No matter the name, they all have one thing in common: they keep scale and stains away.
If you found any of this helpful, or you have more questions please feel free to contact us either by email or phone. Thank you for your time and have a great day.
Halcyon M. Blair Aegean Pools
AQUA Magazine encourages readers' comments. Feedback should include your name, business name, address and phone number. Submit your comments to [email protected]. Submissions may be edited for length and clarity.
