Can anyone tell me what this white stuff is on the very bottom and on both sides of my hot tub flagstone overflow and on the waterline tile directly below it. This is the only place it is on the entire pool. All my numbers are are of good value. I tried rubbing it with a pumice stone before I took this pic. I wouldn't think it is scale as all my values have been spot on since my pool has been built. This is a new pool of about 3 months.
White substance on hot tub flagstone overflow & waterline tile
- Thread starter Calleblanc77
- Start date
It is a mixture of calcium and salt that accumulates when water evaporates off of those areas. The rest of the overflow wall gets wet enough that the water doesn't ever completely evaporate. But near the edge it will get enough spray to get a little wet, but not enough to prevent evaporation from leaving behind all the solids that are in the water.
It should come off fairly easily with a dilute muriatic acid solution.
It should come off fairly easily with a dilute muriatic acid solution.
What dilution rate should I use? I am assuming muriatic acid and water.
Yes, muriatic and water. Add one part of acid to ten parts of water (assuming 31.45% acid). When you have done this a few times, you can use higher concentrations, but they are a little more difficult to work with and you only have a small area to work on.
I'm new to the forum but have experience with using muriatic acid to clean calcium deposits, sometimes called hard water stain. JasonLion's suggestion is exactly what I would recommend. The white spots are not harmful, just unsightly.
I did the suggestions above with Muriatic and water and it took it off my water line tile. Now i am seeing more and more of this coming from my grout above my water line tile and on the rock waterfall mortar and grout on the spa sillover tiles. None of it is on the waterline so i am doubting the CH level is too high. Does this mean that my CH is too high or would reducing the CH help control this? It is a fairly new pool of about 6 mths. My numbers which i feel are all in the correct ranges are below. Any suggestions on how to control this?
CL 3
PH 7.4
TA 65
CH 300
CYA 50
Pool Water Temp 82 degrees
CL 3
PH 7.4
TA 65
CH 300
CYA 50
Pool Water Temp 82 degrees