I have a gunite pool, ~16,000 gallons. The filter went out and it sat for around a year and a half. I know that's not good, I didn't have much choice in the matter... To make matters worse, I used flocculant incorrectly (through the filter) and ruined my sand. I replaced the sand and with the supervision of a professional emptied the pool, scooped all of the gunk and garbage off the bottom and immediately refilled it. I mainly did that because I couldn't see the bottom and I was afraid there still might be floc in the water which would ruin my new sand...
Anyways, I was able to get the water balanced (for the most part) and clear. Now my issue is the picture below. I originally thought it was organic staining (and part of it may be), but now I am pretty certain calcium scaling is playing a major role in the ugly look. I know for that year and a half the pH was sky high 8+ so I'm pretty certain it is calcium scaling with trapped dirt underneath. The discoloration is slightly abrasive to the touch. When I scrub it with a wire brush, a small cloud comes up but the marks are still there. My psi jumps fairly dramatically too. I know enough to be stupid about pool chemistry and I am quickly learning about CSI and it's role in scaling...
Here are my most recent results below:
FAC- 2ppm (CYA of 30 ppm I need this up to 5ppm)
TAC- 2ppm
CH- 250 ppm
CYA- 30 ppm (I'm keeping my eye on it)
TA- 100 pm
pH- 7.7 (trying to get it to 7.5)
TDS- 900
I'm pretty sure if I lower the pH to 7.2 and lower the alkalinity to 80 (and keep my eye on it daily), I can reverse the problem. In a perfect world (balanced 5 ppm FAC, pH 7.2, TA 80, and the rest of the numbers good) the CSI would be -.43. I'm assuming that with daily wire brush scrubbing might rectify the scaling? I'v heard of people rigging 80 grit sandpaper to their brush and lightly brushing?
I know there's a pumice type abrasive tool called a "stain eraser" that hooks up to my pole, I'm just worried its going to scratch the gunite (i'm probably being too chicken).
Scaletec makes a product for this exact thing, but if I'm learning anything it's that TPF does not advise anything beyond basic components for chemistry. Goodness knows I've burned myself a few times trying to take a shortcut.
I'm not sure if I'm on the right track or not, any advice would be really appreciated.
Anyways, I was able to get the water balanced (for the most part) and clear. Now my issue is the picture below. I originally thought it was organic staining (and part of it may be), but now I am pretty certain calcium scaling is playing a major role in the ugly look. I know for that year and a half the pH was sky high 8+ so I'm pretty certain it is calcium scaling with trapped dirt underneath. The discoloration is slightly abrasive to the touch. When I scrub it with a wire brush, a small cloud comes up but the marks are still there. My psi jumps fairly dramatically too. I know enough to be stupid about pool chemistry and I am quickly learning about CSI and it's role in scaling...
Here are my most recent results below:
FAC- 2ppm (CYA of 30 ppm I need this up to 5ppm)
TAC- 2ppm
CH- 250 ppm
CYA- 30 ppm (I'm keeping my eye on it)
TA- 100 pm
pH- 7.7 (trying to get it to 7.5)
TDS- 900
I'm pretty sure if I lower the pH to 7.2 and lower the alkalinity to 80 (and keep my eye on it daily), I can reverse the problem. In a perfect world (balanced 5 ppm FAC, pH 7.2, TA 80, and the rest of the numbers good) the CSI would be -.43. I'm assuming that with daily wire brush scrubbing might rectify the scaling? I'v heard of people rigging 80 grit sandpaper to their brush and lightly brushing?
I know there's a pumice type abrasive tool called a "stain eraser" that hooks up to my pole, I'm just worried its going to scratch the gunite (i'm probably being too chicken).Scaletec makes a product for this exact thing, but if I'm learning anything it's that TPF does not advise anything beyond basic components for chemistry. Goodness knows I've burned myself a few times trying to take a shortcut.
I'm not sure if I'm on the right track or not, any advice would be really appreciated.
