I have had a terrible time with calcium buildup on my pool ever since it was built (14 years ago). Water where we live is VERY hard. Had a guy come out a few months ago who did a decent job using kieserite (for $500). Three months later, it's as bad as ever and I call the guy back and he says it's my water and I should drain the pool and then he'll come out and blast it again (for another $500). So I take a sample to a local pool place and they tell me the same thing because my TDS is "off the scale". They also tell me I should be keeping my TA level at 120 (I've been keeping it about 80). Of course I run everything by this forum, and the unanimous consensus is that TDS is a worthless measure. My water looks great, chemistry is decent (pH = 7.8, FC = 3.5, TA = 80), CYA = 40. Using the pool calculator, I get a CSI about -.3. Pool has not been drained in at least 5 years, but it sure seems to be an extreme step that I'm reluctant to take. Do I just have the blaster guy come back out and do a better job keeping my Ph lower and my TA higher?
Scale Deposits at Waterline
- Thread starter hillyjd
- Start date
- May 3, 2014
- 58,369
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Re: Scale Deposits at Waterline
What is your CH?
If you are having scale buildup that cannot occur at a CSI of -0.3. Are you testing your water regularly?
How are you testing your water?
What is your CH?
If you are having scale buildup that cannot occur at a CSI of -0.3. Are you testing your water regularly?
How are you testing your water?
Re: Scale Deposits at Waterline
CH = 270. I test the water once a week in the winter. Twice a week in the summer. I'm using the Taylor K-2006 test kit. I just bought a new one in April. My numbers align pretty well with the pool company test. But I will admit I let the pH sit around 7.8 - 8.0 most of the time. I think I need to be more aggressive with acid and keep it lower. I usually add acid and baking soda at the same time to try and keep the TA reasonable.
CH = 270. I test the water once a week in the winter. Twice a week in the summer. I'm using the Taylor K-2006 test kit. I just bought a new one in April. My numbers align pretty well with the pool company test. But I will admit I let the pH sit around 7.8 - 8.0 most of the time. I think I need to be more aggressive with acid and keep it lower. I usually add acid and baking soda at the same time to try and keep the TA reasonable.
- Jun 22, 2014
- 47,790
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Increasing the TA would simply be counterproductive as it would encourage the pH to rise faster. From your initial post, I think you understand the concepts. You're right about the TDS, and the pool store will almost always give you their "industry standard" replies about levels. Now it's just a matter of trusting your own testing. I will say though, it's incredible that your CH is so low (270) in that area. Most AZ's struggle to keep it below 700-800. Can you confirm please which test kit you are using? Perhaps add it to your signature as well.
Also, are you using the speedstir to mix the solutions for your CH tests? Some of these questions may be valuable later in the discussion.