Help! My calcium hardness continues to rise

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Are you using the spill-over feature often? If so, it could be exacerbating your pH problem. Anything like fountains, spill overs, jets and the like will cause a pH rise from the aeration they provide. Nice to use when you *want* to raise your pH, other wise..... well...<shrug>

Definitely switch to muriatic acid. It is cheaper, faster, and doesn't cause a build up of sulphites like pH down does when used often.
 
The spill over from spa to pool can't be turned off, at least I don't think it can. I will check. I will get the muriatic acid, thank you.

Can someone help with another problem? I noticed just the other day, there are bumps on the walls of the pool which are a bit crusty on the top, it was not there last year. It's pretty widespread, a couple on the step too. I'm hoping, praying, that is a normal part of the plaster curing process, but I'm worried that its an issue with the plaster bonding. As noted earlier, the pool was opened last year to scale throughout the entire pool, opened this year to the spa scaled and chipped. The installer is coming in a week to polish the spa, they've not responded to this new development. This is only my third season with this pool, it never ends! Thanks to anyone that can help.
If it is a plaster bonding issue, or another big problem, what is the remedy? Thanks!!
 
Susan Rossi said:
The spill over from spa to pool can't be turned off, at least I don't think it can. I will check. I will get the muriatic acid, thank you.

Can someone help with another problem? I noticed just the other day, there are bumps on the walls of the pool which are a bit crusty on the top, it was not there last year. It's pretty widespread, a couple on the step too. I'm hoping, praying, that is a normal part of the plaster curing process, but I'm worried that its an issue with the plaster bonding. As noted earlier, the pool was opened last year to scale throughout the entire pool, opened this year to the spa scaled and chipped. The installer is coming in a week to polish the spa, they've not responded to this new development. This is only my third season with this pool, it never ends! Thanks to anyone that can help.
If it is a plaster bonding issue, or another big problem, what is the remedy? Thanks!!
Click to expand...
Check out Calcium Nodules in pools
 
Thank you for the information, this unfortunately is what I expected. The bumps I have on the walls are pretty extensive, they do not drip as the photo's show though, but they certainly seem like they are nodules from bond failure. I found one yesterday on the steps into the pool that has chipped, I expect I will be finding more and more as time goes on this summer. I have a 3 year warranty on the the pool surface which is good to 4/15/17. What in your opinion should I expect the pool company to do to remedy this in the pool?
They are coming to polish the chips in the spa in a week, I want them to polish the entire spa as it is still very rough from the scale, would you suggest re-plastering the spa? Also, do you think the calcium nodules, and bond failure contributed to the calcium hardness issue I've been having and the pH running high for the past two seasons? I so appreciate your response and any suggestions to remedy this situation or any additional information you can provide. Thanks again!!
 
Yes one of the symptoms of calcium nodules is an increasing calcium level.
A very close look at the nodules is needed to determine whether small cracks are seen. The plaster could have shrinkage cracks which is another reason for nodules to form.
A couple of pictures would help know if that is what is going on.
 
Sorry, sent one photo twice. The bottom one looks like a little volcano up close, it's new just noticed it yesterday afternoon. I can't get close enough to most of the bumps as they're under the water line. I can tell you though they are crusty to the touch, there are new chips everyday. Also my pH is running so high in the past few days, is that a symptom too? I keep adding pH down, going to get muriatic acid this morning.
 
There are two issues going on with your pool. Calcium nodules and scaling. To control/prevent scale you need to manage your CSI between 0 and -0.3. Poolmath will calculate that for you after you enter your test results. High PH is the primary contributing factor to scale problems. PH needs to be kept between 7.2 and 7.8 at all times. Test daily and add acid if necessary to manage it.

A few things contribute to PH rise and can be managed to help slow PH rise

High TA causes PH to rise. Every time you add MA to lower PH it will also lower TA. Or you can actively lower TA following this, Pool School - Lower Total Alkalinity. You probably want your TA around 60.

Aeration increases PH, waterfalls, bubblers, swimming, rain all increase PH. Running water features less will slow down PH rise.

More here, Pool School - Calcium Scaling
 

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Yes calcium nodules also cause the pH to rise, and this should not be confused with a high pH that is causing nodules. Nodules form due to either delamination or cracks, regardless of pH.

Tap near a nodule with plastic handle end of screw driver and listen for hollow sound. Tap away from nodule and listen for hard tight sound. That is an indication of delamination nodules.
 
Thank you onBalance! I read that the pH would rise in your post Calcium Nodules in Pools, wanted to verify. Yes, luckily we do not have overall scaling too. I am getting some traction from the pool installer, they're coming Monday to access the pool 'bumps' to determine if we have a nodules and bond failure. I will try the tapping exercise before they come out. If we have it re-plastered, we will upgrade to another finish not the current white plaster. I may need opinions if that is the case.
Thank you again!
 
We will be having our pool re-plastered due to the chipping, calcium nodules and bonding issues above, the pool installer is honoring the warranty. I will be upgrading my finish from white plaster to either a quartz finish or a pebble finish. Does anyone have thoughts on either of these finishes on a re-plaster job? I'm concerned with the bonding of each. I would also like feedback please, pro's and con's of each finish. I want something more durable, easy to maintain, as well as an attractive finish (I know that's subjective). This is just my third season with this pool and I would appreciate any advice, as I do not want to do this again! I plan on dealing with the chipping and calcium nodules this summer so we can use the pool, and having the re-plaster done in September. Following the re-plaster we would close the pool for the season.... any thoughts on timing of the job? Many thanks!
 
That is great news! Quartz will last 15 to 20 years and pebble will last 25+ years. With proper management of CSI between -0.3 and +0.3 from the start and weekly brushing you can add a decade to the life of the plaster and keep it looking great for decades. Installing a Nationally known product like Pebbletec, NPT or Wet Edge will generally get a better result and better support, if needed.

Here is an article about a quality plaster job. Ten Guidelines for Quality Pool Plaster
 
I had this pool replastered with a pebble finish in 2017, under warranty by the pool installer. My CH continued to rise. In September of 2018 we had 1/2 the pool drained and filled with house water, it has a low CH around 70. Water was 195. Pool was covered, in November the CH was 400. Again in winter the maintenance company pulls the cover monthly to test the water. The pool Was uncovered in April and I’ve noticed the pebbles in the spa are coming off the walls, I noticed the start of scale which I brush off, unfortunately along with pebbles. The CH is 600. The pool installer is coming to look at the spa, but bc the hardness is so high I’m pumping 1/2 water off to lower the CH because Im sure I will be blamed for the spa issue. Again I do not add anything with calcium, but it continues to rise and has done so for years as you can see by previous posting.
Saturday the FC was 3.0, Alk 60, pH 7.5. I use Taylor test kits and have a sped stirrer. Any thoughts or suggestions on the source of the calcium?
 
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