Calcium problem

by Julia

Calcium problem

by Julie
(Atlanta)

We have a large saltwater pool with a hot tub that we heat frequently. We had the pool put in about 2 years ago.

Since the pool's inception, we have had trouble with scaling around the tile line and anywhere the water spills over the stone. We continue to have calcium show up as being low but I am hesitant to add much because of the scaling everywhere. Can you shed some light? Many thanks for any info you can give me.

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Thanks for the question Julie

I've taken care of several pools in Arizona with this issue. They have very hard water there, about 200 - 300ppm, so scaling is an issue.

You can mitigate this by keeping the pH and total alkalinity (TA) in line. With a salt pool you can get away with having the TA a bit lower, down to 60 - 70ppm and keep the pH between 7.4 - 7.6. This is important because it will lessen the effects of the calcium buildup.

I'd like to have your complete chemical readings:

Chlorine, CYA (cyanuric acid/stabilizer), pH, Alkalinity, Calcium Hardness, and Metals (iron and copper). It makes troubleshooting much easier and I can tell what going on.

Now for getting rid of the scaling around the tile. You have some options and I'll let you decide which one or combination you'd like to try.

First is the least invasive. White vinegar is acidic, not poisonous, and can do a good job. Straight vinegar in a spray bottle, a pumice stone and scouring pad.

Next is Comet spray cleanser, pumice stone and scouring pad. Bio-Dex Quart Protect-All Supreme or Salt Protect per 20,000 gallons to the pool water. Pour this into the pool and allow for FILTER for 8 - 10 hours. Sand blasting with glass beads if you can find a good contractor.

Last is the most invasive, but the best. Undiluted muriatic acid in a spray bottle. It fizzes up and will make the rest of the calcium more brittle and easier to scrape. Be sure you wear long sleeves, eye protection, rubber gloves, and a mask. Muriatic acid is one of the most caustic acids and even a couple of drops on your skin can hurt.