How to fix Pool Scale due to calcium

[Nburns1]

I had my pool replastered this winter and I screwed up the startup. Long story short, I added way too much calcium at pool start up and didn't realize the effects it would cause. After about 2 months I noticed the scale appearing but didn't fully realize what it was. It's now been another 2 months and I can't seem to figure out how to get it to go. The scale is on the pool plaster walls, NOT the tile, and is rough to the touch which is why I want it gone. Here's what I've tried, but looking for any advice.

1. Kept PH at 7.2 for about 5-6 weeks now, I've been scrubbing the walls with a steel pool brush 1x per week and my nylon brush 3x per week.
2. I tried putting in Scale-tec for about 3 weeks. It did seem to help a touch and parts of my shallow end are now scale free, but didn't do anything amazing and at a price of ~$50 per week, I stopped
3. Tried pumice stone on various spots, doesn't seem to help
4. Called about 5 different pool companies in the area to ask about acid washing, nobody seems to want to touch it. I got referred in a big circle (Comp A tells me to call company B, B tells to call C, C tells to call A)

My pool size is about 12K gallons. Would draining it and refilling help at all? My calcium is hardness is steady at about 250ppm each time I test

Appreciate any advice you can give!

 

[ajw22]

Draining and refilling will not help scale deposited on the surface.

What test kit do you have? If not a Taylor K-2006C or TFT Test Kits then get one of them.

Post a complete set of test results from YOUR test kit in the format...

FC
CC
pH
TA
CH
CYA
SALT (If you use a SWG)
WATER TEMP
CSI (As calculated by PoolMath)

 

[JoyfulNoise]

Can we also get the longer version of the shortened startup story? Specifically -

What is the pH/TA/CH of the fill water used?

How long after the final troweling was the plaster allowed to sit before filling commenced?

Was any calcium chloride accelerant added to the plaster mix?

What type of plaster is it? Manufacturer? Color/aggregate info?

Was the plaster surface acid washed prior to fill? Pressure washed? Was it polished at all?

What other chemicals did you add after startup and when?

@onBalance should probably take a look at this thread …

 

[ferk78]

Steel brush and plaster are not recommended. Are you sure you are not damaging the surface?
I use nylon only in my pool.

Did you measure your TAP water before you started the fill up?
(It would be great to measure this anyways today, in your case).

The scaling is the consequence of water being over-saturated with calcium carbonate, you need to post all the measurements and calculate the CSI or LSI.
Even if you keep the Calcium Hardness "within range", you can have scaling because your overall CSI index is scale forming.
You will need to bring the calcium scales back into solution (dissolved) by adjusting the CSI (PH plays a major role).

Get the Taylor K2006C (and a magnetic mixer if you can).
(Curious on how did you measure CH 250ppm?).

 

[Nburns1]

I will take measurements of the pool tonight when I get home and report back but wanted to answer a few of your other questions in the meantime. also I think I mispoke my pool is actually closer to 22K gallons.

1. Here's the long story of the calcium issue. I used leslies at the time to help me out with startup, I went there and they gave me the typical print out of add 14 lbs of calcium to your pool and X lbs of acid etc. I did those steps and went back the next week and had a new test taken. Their printer was down, so the guy wrote it on a piece of paper for me. On my way home I was looking at the results on the leslies app and didn't realize that it had not updated. So I was looking at the previous weeks test, and when I got home I added the 14 lbs of calcium needed again.

2. Pool was replastered with Diamond Brite Quartz , Onyx color. Notes on my invoice said "strip plaster to substrate and replaster)

3. Did not measure the tap water. When they finished replastering, they put 2 hoses in the deep end of my pool going into a water bottle with a rag on the end. I had those running continuously for about 36 hours and it was full.

4. Start up was mainly done with weekly leslies tests leading me through it. I added 2 bottles of sequester at the initial fill up recommended by the plaster company. And added another bottle about 2 weeks later. I had to brush the pool 3x per day for the first 2 weeks until the plaster dust was gone. I was not as on top of PH as I should have been. I likely had high PH for the first 2 months, as I didn't realize how fast it was rising. I pay much closer attention now

5. Plaster was not acid washed or pressure washed prior to fill to my knowledge. They finished troweling and immediately filled it with water. No polish either