Whole Pool Stain, Rough Plaster at Season Open

[squirrel49]

Thanks for the replies.

I'm pretty sure you're all right on the mark. I think it is calcium scale. I went swimming tonight with a snorkel mask and inspected most of the pool. The surface is extremely rough (feels crystaline). It covers the entire pool, other than the foot or so that was not under water over the winter (that part is smooth). On the bottom, and all steps, it is tan, and on the walls and vertical surfaces it is white or colorless. I have a Merlin mesh safety cover that lets in fine silt over the winter so I think what I have been calling stain is actually dirt-covered calcium scale. This did not happen in prior years, but I don't remember opening at such a high ph level before.

I am willing to do whatever it takes to get rid of it. I would like to try every alternative other than draining the pool. The pool is appox 28K gallons and costs ~ $900 in fill water to fill it. I'm sick to my stomach because our pool plaster has always been baby smooth and now it feels like volcanic lava.

I will first try dropping the PH to ~ 7.0 and do a lot of brushing. So far brushing doesn't seem to do too much. I only have a nylon brush, should I buy an aluminum one? Is there anything else I should be doing? I don't know that a pumice stone is an option. The scale seems to be on every square inch of the pool.

Btw, my cya level is ~50.

Thanks,

Pat.

[Lenny]

Have you had any luck, Pat? I have the same problem, although maybe not as bad as you. Tan stains and roughness. I have a mesh cover too.

This is my second opening. The first closing was right after completion of the build, so I think my plaster has still been curing and causing my PH to get high very fast after closing. Both years my PH was sky high upon opening and my hardness and alk were both low.

Tomorrow I'll try dropping the PH and giving it a good brushing.

[squirrel49]

No luck yet. Consensus seems to be that I will have to drain and light acid wash or sand/buff to remove the roughness. I am trying anything I can to avoid that. The pool is relatively new (2 1/2 years).

We have dropped the PH and we brush twice a day now and my wife optimistically thinks is is getting slightly better --- I don't really see any difference yet.

This is my second opening as well, both with a mesh cover. One difference is that the first year I had not yet started the salt system on my pool, so it was closed and opened as a fresh water pool. Opened fine, plaster as smooth as ever. I brought the Salt system on-line last year, so this was the first year it was closed/opened with salt water. Could this be a contributor? Are you running a SWG?

[Lenny]

I am running a SWG and installed it last year.

But there are so many people around here who've been using these. I've gotta think the word would be out if that was really a contributor.

[Lenny]

Actually, I wonder whether the mesh cover has more to do with it. I pumped my water down a good 16 inches at closing and it filled up pretty quickly this year. I even pumped a bit out at one point. And then if was full to the top again by the time I opened.

By the time I open my hardness and alk are very low. I'm thinking I'd have been better off with a solid cover that keeps the rain water from diluting the pool water. Not sure what the alk and hardness of rain water are, but I'm thinking it's not optimal

[squirrel49]

Lenny,

I've had the mesh cover since I built the pool.

1st year, no SWG running, drained 18" water and closed pool. Over the winter, water level rose, I drained again at one point in the spring, prior to open. Opened to clear water, silt, worms etc on bottom. Vacuumed, shocked, balanced water, everything was great, plaster was clean and smooth.

2nd year, SWG operational, drained 18" water and closed pool. Over the winter water level rose, I drained again at one point in the spring, prior to open. Opened to clear water, silt, worms etc on bottom. Vacuumed, shocked, balanced water, but this time everything was not so great. Extremely rough pool walls and bottom with the horizontal surfaces tan/stained in color. To date, nothing has been successful in removing.

My in season water balancing, closing, and opening procedures did not change at all. I am not convinved that the SWG and saltwater pool had anything to do with my problem, but it is the only change I am aware of, so it at least makes me curious.

Pat.

[waterbear]

The difference might be that you did not keep close watch on your pH once you installed the SWG. They have a tendency to cause pH to rise and if you let that happen you could create scaling conditons.