Calcium scale and negative CSI in fiberglass pools

seribus

Active member
Jun 9, 2016
31
Spring Lake, NC
#21
Hi drseuss, I've thought calcium scale of both kinds until recently I started thinking oxidation. Tallman at first pointed me to swg causing it and had me pour in Jack's magic. This past visit they balked at oxidation and said it was something on the surface due to chemistry. I even went as far to call pentair about my swg and they sent brand new one out. Using it now. Going back to chlorinator didn't help either. I can see a slight water line where I brought down pool water level for winter and to be honest it may be better above that level but not 100% sure. Maybe winterizing chems are doing something. I used 'In The Swim' non chlorine winterizing kit to close each year. Chalky look has covered most everywhere and although it's still blue it's not the nice shiny Pacific blue it was in year 1. I hope one of us figures it out. Brushing doesn't help. Nothing wipes off. I can sand it and see the white dust trail. Sometimes on the sandpaper I see a faint light blue residue which makes me think oxidation. Imay push Tallman to come out in fall and buff it.
 

seribus

Active member
Jun 9, 2016
31
Spring Lake, NC
#22
Texas,

I have thought calcium silicate too. Back 2016 I thought that but was miffed how quick it got there. Since then I would think I wouldn't get anymore scale with the way I've kept pH on low side. I think what I see in the seats and ledge curves is silicate. What grit paper are you using? Do you close in winter? I wonder if we skip closing and run csi negative it will eventually disspate? It would be nice to rule out scale vs oxidation and know 100% the culprit. Sanding it tough and low on grease as well.
 

seribus

Active member
Jun 9, 2016
31
Spring Lake, NC
#23
Drseuss, I'm in NC and had pool installed from a company out of Cary area. Not much if any help from installer or manufacturer. My calcium was always very low around 30-40 range years ago when issues started. Last year I brought that up and maintained it. In some areas I can still see the dark blue so it's not completely uniform in coverage. Those areas trick me into thinking maybe it's getting better or then again maybe it's getting worse. Hard to tell anymore.
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
#24
Texas,
I have thought calcium silicate too. Back 2016 I thought that but was miffed how quick it got there. Since then I would think I wouldn't get anymore scale with the way I've kept pH on low side. I think what I see in the seats and ledge curves is silicate. What grit paper are you using? Do you close in winter? I wonder if we skip closing and run csi negative it will eventually disspate? It would be nice to rule out scale vs oxidation and know 100% the culprit. Sanding it tough and low on grease as well.
Out of frustration and as an experiment of sorts for myself, I ran my CSI very, very low last season and throughout the winter. At times I thought there may be changes, but later determined it was just some wishful thinking, and perhaps some tricks on my eyes. When I create my own thread about everything later (w/ pics) you'll see what happened to my shell color. I'm still doing sanding around the perimeter of my pool and other places that I can reach as time permits each day. In my situation, I'm using a 3M 120 grit wet/dry to remove the initial chalkiness, then once I'm back to blue I follow it up with a few strokes of 400 grit wet/dry - bay smooth. In my situation, it seems to be a good combination. But I tell you, it is absolutely amazing how much of that chalky substance, which I have to assume to silicate, is removed. I have a dust blanket on the pool floor and have to rinse my cartridge frequently as I push the dust to the filter. In an ideal situation, I would rain the pool and use power tools, but I don't have that ability at the moment. So for now, I'll do a little sanding each day (very exhausting) and simply pace myself to where I'm satisfied. Once I get to a point where the only places left are deep, I'll rethink my options. I'm still a bit puzzled by the aggressiveness of that chalkiness and how it got on my shell. If silicate as I assume, there's no doubt it had to be a combination of elevated pH with our local hard water. The first 2 years or so before I came to TFP, I focused on algae control mostly and simply ignored the consequences of scale. It didn't happen overnight, so I suppose it just finally hit me. But I'm keeping good notes, pics, and a timeline of what I'm going through to share later.
 
May 30, 2018
12
Pittsboro, NC
#25
Hi seribus, I'm with you on the calcium. Now thinking it's oxidation. Is yours smooth or rough? Ours is smooth which makes me think oxidation, however nothing comes off on the hand. Have to use sandpaper as well. We bought from Cool Pools. No help. I tried Jack's Magic and it did nothing. I'm now trying Scaletec, but not seeing much. We did go out this morning and the water was cloudy, the first time we've seen that, so not sure if it's the Scaletec or if Scaletec is eating our chlorine. We don't winterize, but switch to Trichlor tablets in the winter. Looks like we only live about an hour away from you, so not sure if it's an area water issue. I sent a note to the pool guy helping us and asked him about increasing CH and he said to do it and that's what he is thinking might be the problem. He's sent our information to the NPC, whatever that is, but hasn't heard back yet. This is our first pool and when Cool Pools came out to give their tutorial they said only test chlorine and pH. My husband actually asked about CH and they said not to worry with fiberglass pools. Lesson learned. We were also moving into our new home at the time and that took most of our time. I'm attaching a photo we took and sent to Cool Pools when we thought it was fading. Not easy to see, but you should be able to see how the edge of the seat is original color.

IMG_5349.JPG
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
#26
Soon, I'll post an update to my own thread as to what I have going on and my theory. Not perfect, and still a work in progress as you can see from these two pics:

Before sanding (this was my water-drop prep for the warranty company review):

Step Area - 12 Apr 18.jpg
After sanding:
3 Jun 18 (4).jpg

I purposely left the surface of the steps lighter because they were acutally so hard to see as the same color, people were mis-stepping and falling down going into the pool. So we're leaving our steps and benches 2-tone.
 
May 30, 2018
12
Pittsboro, NC
#27
Hi Pat,
I'm really not looking forward to what you are doing. It looks like a massive job! I stopped by Lowes to pick up some 600 grit wet/dry sandpaper today to see what it does in a small spot but haven't tried it yet. Is there any risk to the gelcoat by sanding with 600 grit sandpaper? If not, I've got a shower scrubber that can be submerged in water. I might try to rig up something with the sandpaper and see if it works. That would be a lot better than by hand. I agree with you about the steps. Wish there was a better way to see them.
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
#28
Is there any risk to the gelcoat by sanding with 600 grit sandpaper? If not, I've got a shower scrubber that can be submerged in water. I might try to rig up something with the sandpaper and see if it works.
Well, when I first brought the issue to the attention of my installer, they had me spot test an area with 600 grit, so I figured what the heck. It couldn't get any worse. I've tried nylon scrubbers and such, but they seemed to leave some tiny streaks and weren't as consistent with the results. Soon I'll get to a point where I stop because obviously I can't sand my entire pool by hand. I wanted to address some specific areas immediately, not only for my own visual benefit, but to see what happens next. I will outline what I've been doing in my own thread soon so I don't hijack seribus's thread. When I do, I'll post a link so folks can go back & forth to compare everyone's experiences.
 
May 30, 2018
12
Pittsboro, NC
#31
I've tried full strength muriatic acid, ascorbic acid, magic eraser, 3m Scotch Brite scouring pad, all of Jack's Magic stain id tests, Jack's Magic #1 with the purple stuff in whole pool and now double strength Scaletec. Nothing, so far, has worked except sandpaper. I'm open to any other suggestions besides sandpapering the whole pool.
 

seribus

Active member
Jun 9, 2016
31
Spring Lake, NC
#32
I called Jack's magic and tried the stain id test just now and nothing. Not even a little bit. Guy at Jack's said if this doesn't move it it's something else like anomaly in gelcoat. I'm thinking oxidation now.

Drseuss, cool pools did mine too. I'm just above Fayetteville. They were less than helpful in most my issues once they got their money unless you want to spend more. I got the same lame instructions you did. Same year I put pool in we had a lot of rain which caused the ground they didn't pack well to sink in. That left concrete floating which eventually cracked. Of course I got the 'all concrete cracks' explanation.

Back to this issue, I was hopeful with stain id test but another strike. I was hoping the copper scale stuff would raise the scale but nope. It's smooth and doesn't come off unless I use sandpaper and when I do use sandpaper you can see a small trace of light blue color on sandpaper. Again makes me think oxidation.

I can try double dose of scaletec but I think I'd just be wasting money at this point. I think Tallman needs to come buff it. Two pools with same issue from same installer....
 
May 30, 2018
12
Pittsboro, NC
#33
I don't think Cool Pools packed well beneath our pool. We can stomp our foot and hear that it's hollow. I'm not sure if this is normal, but it seems like it wouldn't be. They also talked us into travertine tile coping. It has completely cracked and is crumbling. We had a concrete overlay guy out and he said they didn't leave enough space between the tiles so they expanded and cracked. Cool Pools did say they would replace them for free but aren't acknowledging that the space between them is the issue. They say it's because of the salt in the pool, which they knew we were getting a salt system. Cher told me we are supposed to wash the travertine tile twice a week. I never heard that before. So, I'm not sure I want them replaced if it's just going to crack again. That's why we are thinking of going with concrete overlay.

The Scaletec doesn't seem to be working for us, so I wouldn't waste your money. I called Tallman and told them about Cool Pools and the advice they gave us. She said she would have Brittany call about repairing the pool. I still haven't gotten that call, so I'll try to call them again this week.

Here's some pictures of our tile.

IMG_5346.jpg IMG_5343.jpg
 
May 30, 2018
12
Pittsboro, NC
#35
Hi seribus,
We ended up going to the College World Series at the last minute and had company through the 4th so I haven't gotten a chance to work on this issue until today. I hadn't gotten a call back from Tallman, so I called them. They asked me to send them some pictures and that they were going to talk to Mr. Tallman about my issue. It turns out that there is an issue with the gel coat manufacturer for pools manufactured between 2014 and 2016 used with salt water systems. It's not just Tallman, but many different pool manufacturers that have used this gel coat. Also boats. There is a company conducting tests right now to determine what caused the issue and how they are going to fix it to prevent this in the future. They asked for my patience while the testing is done and hopefully completed by the end of the month. They have promised to fix the issue once they have their plans in place. The indicator for them was the three stripes on the bottom of the pool. It must have to do with whatever product is used in those areas. They believe that the gel coat is holding water. So, not sure if this applies to you, but you may want to give Tallman a call and see if it does. It was driving me crazy trying to figure out what I was or wasn't doing to cause this. I'm feeling a whole lot better now!!
 

seribus

Active member
Jun 9, 2016
31
Spring Lake, NC
#36
Hi Drseuss,

After reading your post I also called Tallman. It is a big relief its not scale or something I was doing to the pool but I guess this issue could drag out. Just a piece of mind it wasn't my pool care that caused it. I think if we stay on this together we might get it resolved. Thank you so much for the info. When I called the lady she said they get quite a bit of calls on this issue. I hope they get it sorted and contact us without us having to chase them down every few weeks.
 
May 30, 2018
12
Pittsboro, NC
#37
Hi seribus,
I'm so glad your issue is going to be resolved too! I'd rather wait for the off season to have it fixed since we swim every day, but when they come a calling, we're having it done. She said to give them through the end of the month, so I won't contact them until August to see where they are with their plan. I also finally got Cool Pools to agree to fix the travertine tile. Apparently, she wrote up a response to me but never sent it. We'll have to wait until their off season to have it done, but that's ok if it's free. I guess we'll have to be extremely careful with the coping once it's fixed. We didn't really want something that took that much work, but not much we can do now. I'm also having a problem keeping free chlorine in the pool. I found out that it's due to phosphates. It may be due to our water, or maybe all the chemicals I was using to try to fix the "haze" issue. We've brought the phosphates down and now the free chlorine is much better. I'll keep you posted if I hear anything more from Tallman.
 

seribus

Active member
Jun 9, 2016
31
Spring Lake, NC
#38
Texas,

i was told by the manufacturer that this is an issue not just with Tallman pools but Viking and others with the gelcoat producer. Like Seuss mentioned I was told the same. Have you reached out to them to see what they say recently?
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
#39
Texas,

i was told by the manufacturer that this is an issue not just with Tallman pools but Viking and others with the gelcoat producer. Like Seuss mentioned I was told the same. Have you reached out to them to see what they say recently?
No, I haven't. From your descriptions above, my situation seemed a bit different as I don't have those 3 stripe indicators that some of you appear to be having. But I'll monitor things and watch your thread for updates to consider my options. Thanks!