I think I have Calcium Crystals not scale after opening new pool

[Liz315]

Hi, so we just opened my pool and looking down at my pool from a slight angle it looks like air bubbles on the pool wall. When I get closer and feel it they are clear sea salt like granular pieces. Feels like it too. I know it’s not salt but it was the best way to describe the look/ size and feeling. When I brush at it with my hand it does come off. The water is still very cold. I’m clueless. My water numbers seem good, water was clear at open. I do have some white calcium on some of my waterline tile but that’s white and this is clear. My CA is 325.

 

[ajw22]

Sounds like scale.

It happens from your pH getting high during the winter when the pool is closed.

Brush the walls regularly and run a low CSI of around -0.6 for a while and it should melt off.

 

[Liz315]

Thanks sounds about right. First pool, first opening and after last season you all taught me so much now after the opening and finally actually experiencing a VS pump the stuff you guys explain is making sense. Thanks for everything. I still have so much to learn, so thankful to have you all.

 

[Liz315]

How do I avoid scale next season? Do I need to test during winter and add acid? How do u do that and mix it around with pump off?

 

[ajw22]

How do I avoid scale next season? Do I need to test during winter and add acid? How do u do that and mix it around with pump off?

You can't easily add acid to a closed pool. Especially if it has snow or ice on the cover.

When was the pool plastered?

On your Pool Math logs I see high pH and high CSI in September and October going into your closing. You need to run your pH lower and your CSI between 0 and -0.3. I think your scaling started before your closing.

 

[Liz315]

It’s one year old. Pool was built last spring. I never really had accurate csi numbers because I don’t easily have my pool water temp. Plus when I did know temp since I like it around 83 when heated it always read high even if other numbers were within range only was it seemed to drop was to have cold water. I need to read more on how csi is effected. Thanks.

 

[ajw22]

One year old plaster is part of the problem. IT should be less of a problem as your palster finished curing.

Calcium Saturation Index (CSI)

How is CSI calculated? Very simple – use our PoolMath tool. To ensure long plaster life and save money, click here to learn more.

www.troublefreepool.com

CSI and LSI - Further Reading

www.troublefreepool.com

 

[Liz315]

Thanks again.

 

[Liz315]

So after looking into calcium scale (which I know I have and get on my waterline tile) I believe what I really have are calcium crystals on my plaster. Here is an article I found and it looks like exactly what I have. Anyone deal with this and have suggestions? My calcium has never been extremely low. At open it reads 325. It I think was 350 at closing unless something is wrong with my reagent.

Calcium Crystals vs. Scale

Calcium crystals grow out of plaster surfaces in pools during the winter. Most are calcite, but there are many forms. Learn how to prevent crystals in your pool.

blog.orendatech.com

 

[ajw22]

@onBalance any thoughts?

 

[Dave1096]

Does it look like this? Here's my 1 year old pool with little "sea salt" looking crystals after opening. Brushing seems to be working, and my robot has picked up a ton of them. I think you're right on it being calcium crystals. Hopefully just a new plaster issue.

 

[Liz315]

when I first opened I didn’t realize it was an issue so I didn’t really pay attention to what was inside it was a lot of those flyer seeds so I think there was some but not so much it made me wonder what it was. I’ve ran it 3 times already so I gotta check the basket again. Yours looks like the long strand version that they say is easier to get rid of mine look the the harder to remove kind so small bumps all along walls so maybe that’s why it’s not picking up with vacuum.
What I don’t get is based on that video which explains it well. I don’t get how I can have scale at waterline tile (said to be caused by too much calcium the water can’t hold and it comes out onto the surface as deposits) then not enough calcium on plaster at the same time (causing the pool water to pull it from the gunite forming the crystals)? This doesn’t seem like fun.

 

[onBalance]

See this article I just posted.

Why Are Calcium Crystals Forming in Pools?

In recent years, calcium crystals have been forming during the winter at a higher rate in some newly plastered swimming pools. From the reports we have heard, this problem seems to occur more often in the northeast of the country. Apparently, pool builders, plasterers, and service techs involved...

www.troublefreepool.com

 

[Liz315]

Thanks for taking the time to write this.

Your words here: “Are some plasterers adding extra calcium chloride to plaster mixes during colder temperatures to speed up the plastering process, so that it doesn’t take all day? Does this lead to calcium hydroxide and calcium chloride dissolving out of plaster regardless of the water balance, thereby increasing the pH, alkalinity, and calcium levels? Could this be a recipe for calcium crystals to develop? Yes.”

Has been my concern since the beginning. My gunite was done in February. It was cold and the builders didn’t seem the least concerned with heating it under a tarp to cure etc. then I noticed the entire shell was leaching calcium while it sat waiting for plaster. They told me it didn’t have to be removed before they tiled and refused to clean it even though I asked them due to my concerns of it coming through the grout etc. well it has and continues to. Now the actual plaster part of the pool they acid washed prior to it. Now this might explain why I have the tile grout area leaching calcium scale white stuff and the plaster area with these clear calcium crystals.
Not sure if it’s that but only way I can make sense of the 2 happening at the same time even though they seem to be opposite problems. Maybe if this happens most to northeastern pools with gunite done in winter that could be our answer.
Where do you suggest I go from here with both issues? My calcium level doesn’t seem to be high or low. Do I drop it to satisfy grout calcium or increase it to work on crystals? What would I even increase it to since it’s 325?

 

[onBalance]

What happens with gunite application problems does not necessarily transform to (affect) the plaster applications. You need to separate the two issues. For the most part, plaster covers up many problems with the gunite.
I don't know what problem you are having with the tile grout. Providing some photos of the tile grout problems may help to diagnose.

The good news is that this wintertime crystal problem probably won't occur again next year because the plaster has more fully hydrated. The only exception to this is if the plaster quality is really poor and defective. Then it might occur a time or two in the future. Therefore, remove the crystals as best you can this Spring and that should be the end of it. It would help to ensure that it doesn't happen next year by brushing the pool and circulating the water as late as possible in the winter and as soon as you can in the spring. The stagnate water is a contributor, but not the reason or cause of this problem.

I believe Orenda is wrong about the cause of these wintertime crystals to develop. It is not caused by aggressive water, but is most likely caused by poor quality pool plaster and workmanship. Orenda is a good company and I believe they will eventually amend and correct their blog on this topic.

 

[Liz315]

Do you recommend me increasing my calcium at all? I’m tempted to try the remover they suggest because it’s so hard to brush off alone. Is there a reason you would suggest not to use it?

 

[onBalance]

I wouldn't raise the calcium level. A calcium level of 325 ppm is considered a good level.

 

[Liz315]

So it is in my robot cleaner. Not a ton but enough to confirm. I can actually scrap it off with my hands and nails obviously hurts but it won’t come off with the stainless brush. I’m guessing it’s the flex of the bristles. So I’m going to use a plastic scrapper hoping to find one I can attach to a pole as the water is freezing.

Just a thought. Could the cold water be why it’s not dissolving into the water and instead freezing almost on the surface? Probably not but curious why it does it in the cold months only.

 

[Liz315]

Ice scrapper works perfect if anyone else needs something to get rid of it.

 

[onBalance]

In addition to the plaster mix containing too much calcium chloride and bleeding out, the crystals form during the winter because of the lack of water circulation and brushing, even by the robot cleaner (assuming you didn't run it during the winter). Cold water actually makes calcium more soluble, not less. Just the opposite of other compounds.