Ok, figured as much - just couldn't figure out how Liquid Chlorine would do any damage to a gel coat - chlorine is chlorine, etc.
Thanks for the clarification.
Thanks for the clarification.
White chalky residue on fiberglass pool
- Thread starter captjohn
- Start date
Jenischmeni - can you please give an update on your situation?
I'm having an identical situation as you and would be interested to know if increasing the CH and use of the Leslie's product worked, "Ultimate Scale and Stain Control"
I'm having an identical situation as you and would be interested to know if increasing the CH and use of the Leslie's product worked, "Ultimate Scale and Stain Control"
Hi skillset! Yes, Leslie's Ultimate Scale & Stain Control did work. (It's blueish colored in a clear bottle and runs about $40. I bolded the "control" because there's also a "remover".) I doubled the initial dose (which was what the label said could be done). I've now added a 2nd dose a month later. We helped it along by brushing and scrubbing. We'd scrub the dickens out of it and the water would turn to milk. About 24 hours later, we'd add some clarifier and it would clear right back up.
We did this about once a week for a few weeks.
Now, the sides feel differently below the water than they do above the water but you cannot get any white to come off on your hands or on make any clouds in the water. I have a gut feeling that I've damaged the gel coat because it went on for so long. I don't think the product did it. (Because it felt a lot worse before I had added the product.)
We did raise the calcium hardness up to around 300 using hardness plus. We had tried the deicer thing but it just wouldn't raise it high enough.
So...between raising the calcium hardness and the Ultimate Scale & Stain Control, I am really, really happy. The slight difference in the feel of the walls above and below the waterline isn't enough of an issue to be bothersome and probably nobody would notice but me. What's really important is that you don't get white stuff on you wherever you touch the walls. I could be wrong and maybe the stuff will eventually get back down to the gel coat. Only time will tell.
We did this about once a week for a few weeks.
Now, the sides feel differently below the water than they do above the water but you cannot get any white to come off on your hands or on make any clouds in the water. I have a gut feeling that I've damaged the gel coat because it went on for so long. I don't think the product did it. (Because it felt a lot worse before I had added the product.)
We did raise the calcium hardness up to around 300 using hardness plus. We had tried the deicer thing but it just wouldn't raise it high enough.
So...between raising the calcium hardness and the Ultimate Scale & Stain Control, I am really, really happy. The slight difference in the feel of the walls above and below the waterline isn't enough of an issue to be bothersome and probably nobody would notice but me. What's really important is that you don't get white stuff on you wherever you touch the walls. I could be wrong and maybe the stuff will eventually get back down to the gel coat. Only time will tell.
Many thanks for the very fast reply!! I feel like I've found folks with the same issue, which in itself, is comforting. I scrubbed quite a bit myself and the water clouded up but did not turn milky white. By cloudy, I mean it became difficult (not impossible) to see end-to-end. Sounds like you had it worse than I currently do. I'm trying to resist putting more stuff in the water, so what I may try to do first is get my CH up. I've owned the pool 7 years and have never maintained CH. I'm not sure I understand the chemistry of why the absence of CH make the scale, but sounds like you've corrected the core issue with CH.
A few questions if you don't mind:
Assuming you added the CH as your FIRST step?
Did you pool cloud up when adding the CH or Scale Control?
Do you feel you needed the clarifier? I am using a slime bag (filters to 1 micron) which has done a decent job clearing the pool from the residue.
Are you saying the fiberglass above the water is "worse"? I have tile, which sits 1/2 in the water and 1/2 out of the water. Curious as to what it feels like? I've noticed that some of the fiberglass feels smooth (like new) while other spots feel slightly coarse. I wonder if this is related to low CH?
I have a tub of Hardness Up in my shed that hasn't been opened in 6 years. Obviously, has gone through temperature extremes. Anyone know if this is still usable?
A few questions if you don't mind:
Assuming you added the CH as your FIRST step?
Did you pool cloud up when adding the CH or Scale Control?
Do you feel you needed the clarifier? I am using a slime bag (filters to 1 micron) which has done a decent job clearing the pool from the residue.
Are you saying the fiberglass above the water is "worse"? I have tile, which sits 1/2 in the water and 1/2 out of the water. Curious as to what it feels like? I've noticed that some of the fiberglass feels smooth (like new) while other spots feel slightly coarse. I wonder if this is related to low CH?
I have a tub of Hardness Up in my shed that hasn't been opened in 6 years. Obviously, has gone through temperature extremes. Anyone know if this is still usable?
This problem of chalkiness was addressed at the same time as another issue - replacing our salt water generator. So, my steps might seem a little odd but it was based upon some other factors.
Since we were replacing the SWG and had to lower the salt content of the pool, we needed to drain 1/3 - 1/2 of the water. (We were reducing from 5000ppm to 3500ppm.) Hubby decided that since we were draining down so much, he wanted to drain it down far enough to caulk around the skimmer, light, and return jets. (Which meant we drained about 2/3rds of the water.) Our goal was to get the water at the optimum levels before putting on the new SWG so that the new SWG could 'hit the ground running'.
After the caulking had dried, I started refilling the pool. Immediately after I started the fill process (literally - the moment the hose was dumping water into the pool), I added the initial dose (but doubled as per the instructions) of the scale & stain control.
It took about 6-7 hours to fill completely and around hours 4-5, I started noticing these white flakes floating on the top of the pool. (The filter still wasn't running yet as the water wasn't high enough.) If I tried to pick one up, it would wrap around my finger like shrink wrap. If I rubbed it, it would rub into a white, chalky, residue. I think it was that crud on the sides already starting to disintegrate.
Once the filter started running (we turned it on and let it run for the next 24-48 hours non-stop), we dumped in the hardness plus. (Adding a little less than recommended. We always do this because it seems like every time we add the recommended amounts, we overshoot the target.) So, there was only about 6-8 hours between adding the two products.
No, the pool did not cloud up when adding either of these products. It did not get cloudy until we scrubbed the sides. It would cloud up enough though that you couldn't even see the bottom of the pool. It would dramatically subside within about 24 hours but clarifier cleared it up completely within an hour or two and returned the water to a beautiful, sparkling state. Did I need the clarifier? I dunno. We have this product, have used it for years and love it. I think it does a nice(r) job of making the grit and bugs fall down to the bottom of the pool and keeps the water sparkling. Do I think my filter could have done it? Yes, it probably would have eventually.
Quote: "Are you saying the fiberglass above the water is "worse"? I have tile, which sits 1/2 in the water and 1/2 out of the water. Curious as to what it feels like?" No, just the opposite. The fiberglass above the water is perfectly smooth and slick. The fiberglass below the waterline is rough. (It feels like a very, very, very fine sandpaper.) It's rough enough in some spots (I think where the return jets tend to send the water) that you can actually feel your swim suit kind of catch on it. Those same areas are where I could get the most stuff scrubbed off and I think it's the spots that were the worst. I can scrub on them with a brush or magic clean eraser and get them smoothed down better after each scrubbing. There is no section, though, where I think I have scrubbed off all the way down to the smooth, silky, feel of the fiberglass equal to how it feels above the waterline with the exception of the seating area. The actual part that you sit on feels as smooth as the above-water-fiberglass but I think that's because our rear-ends have kept that polished for years :-D The sides leading up to the bench feel like the rest of the pool - slightly rough.
I cannot answer your question of whether the calcium hardness can go bad over years. I'm not a scientist (and I haven't even stayed in a Holiday Inn Express in years!) I would guess that it's probably fine though and may only have clumped up and a bit harder to dissolve. Just my guess though.
Please keep me updated though and I'd love to hear how this turns out for you.
Since we were replacing the SWG and had to lower the salt content of the pool, we needed to drain 1/3 - 1/2 of the water. (We were reducing from 5000ppm to 3500ppm.) Hubby decided that since we were draining down so much, he wanted to drain it down far enough to caulk around the skimmer, light, and return jets. (Which meant we drained about 2/3rds of the water.) Our goal was to get the water at the optimum levels before putting on the new SWG so that the new SWG could 'hit the ground running'.
After the caulking had dried, I started refilling the pool. Immediately after I started the fill process (literally - the moment the hose was dumping water into the pool), I added the initial dose (but doubled as per the instructions) of the scale & stain control.
It took about 6-7 hours to fill completely and around hours 4-5, I started noticing these white flakes floating on the top of the pool. (The filter still wasn't running yet as the water wasn't high enough.) If I tried to pick one up, it would wrap around my finger like shrink wrap. If I rubbed it, it would rub into a white, chalky, residue. I think it was that crud on the sides already starting to disintegrate.
Once the filter started running (we turned it on and let it run for the next 24-48 hours non-stop), we dumped in the hardness plus. (Adding a little less than recommended. We always do this because it seems like every time we add the recommended amounts, we overshoot the target.) So, there was only about 6-8 hours between adding the two products.
No, the pool did not cloud up when adding either of these products. It did not get cloudy until we scrubbed the sides. It would cloud up enough though that you couldn't even see the bottom of the pool. It would dramatically subside within about 24 hours but clarifier cleared it up completely within an hour or two and returned the water to a beautiful, sparkling state. Did I need the clarifier? I dunno. We have this product, have used it for years and love it. I think it does a nice(r) job of making the grit and bugs fall down to the bottom of the pool and keeps the water sparkling. Do I think my filter could have done it? Yes, it probably would have eventually.
Quote: "Are you saying the fiberglass above the water is "worse"? I have tile, which sits 1/2 in the water and 1/2 out of the water. Curious as to what it feels like?" No, just the opposite. The fiberglass above the water is perfectly smooth and slick. The fiberglass below the waterline is rough. (It feels like a very, very, very fine sandpaper.) It's rough enough in some spots (I think where the return jets tend to send the water) that you can actually feel your swim suit kind of catch on it. Those same areas are where I could get the most stuff scrubbed off and I think it's the spots that were the worst. I can scrub on them with a brush or magic clean eraser and get them smoothed down better after each scrubbing. There is no section, though, where I think I have scrubbed off all the way down to the smooth, silky, feel of the fiberglass equal to how it feels above the waterline with the exception of the seating area. The actual part that you sit on feels as smooth as the above-water-fiberglass but I think that's because our rear-ends have kept that polished for years :-D The sides leading up to the bench feel like the rest of the pool - slightly rough.
I cannot answer your question of whether the calcium hardness can go bad over years. I'm not a scientist (and I haven't even stayed in a Holiday Inn Express in years!) I would guess that it's probably fine though and may only have clumped up and a bit harder to dissolve. Just my guess though.
Please keep me updated though and I'd love to hear how this turns out for you.
I appreciate very much your detailed response. Guess we all can learn from each other.
Sounds like we have similar issues with the FG with the residue and white flecks. Today, I started adding the CH. I'm probably up to just under 200 and I think I will stop there. My pool didn't cloud with the addition, so I'm glad about that. Pool wasn't bad today - I've been running the filter 24x7 now for weeks with a slime bag as recommended by ChemGeek. It's doing a very good job clearing the pool - but not getting the full clearing in an hour or two like you did with clarifier. I can be a bit patient as there is just a slight haze now in the pool - I wouldn't call it cloudy.
The big next step for me is to give the pool another very good scrubbing, which I'm sure will recloud the pool, but hopefully not as bad. Once that clears, I'm hoping I'm done and the CH may solve the issue so it's not continuing. I haven't seen white flecks today after adding CH.
I can relate to the "feel" issue. In many part of the pool, it feels a bit course, not like the original smooth fiberglass. But, I can live with it as it's not too bad. Sounds like, though, you were able to brush some of it "smoother." Good tip for me to experiment.
Which clarifier to you use ?
Thanks again !
Sounds like we have similar issues with the FG with the residue and white flecks. Today, I started adding the CH. I'm probably up to just under 200 and I think I will stop there. My pool didn't cloud with the addition, so I'm glad about that. Pool wasn't bad today - I've been running the filter 24x7 now for weeks with a slime bag as recommended by ChemGeek. It's doing a very good job clearing the pool - but not getting the full clearing in an hour or two like you did with clarifier. I can be a bit patient as there is just a slight haze now in the pool - I wouldn't call it cloudy.
The big next step for me is to give the pool another very good scrubbing, which I'm sure will recloud the pool, but hopefully not as bad. Once that clears, I'm hoping I'm done and the CH may solve the issue so it's not continuing. I haven't seen white flecks today after adding CH.
I can relate to the "feel" issue. In many part of the pool, it feels a bit course, not like the original smooth fiberglass. But, I can live with it as it's not too bad. Sounds like, though, you were able to brush some of it "smoother." Good tip for me to experiment.
Which clarifier to you use ?
Thanks again !
Thanks.
I called San Juan today, the pool manufacturer. They said the pool does not need CH. I said that was odd since my owners manual called for a range of 300-350! I asked about what could cause the white residue and the rougher patches of fiberglass. The white residue is often attributed to too much CH in the water, but this was not the case for me. Perhaps for me, the residue was some Alum floc that dried on the pool surfaces when I unsuccessfully tried to floc the pool a few weeks back. The rougher patches were not really explainable other than having a lower/higher than normal range alkalinity for a period of time. But, I do not think I have this issue either given I'm testing Alk once a week.
The remedy for both was to scrub the pool. Using a 1000 grit sand paper was suggested to use on the rougher spots. Given the pool has a 32 mil gelcoat it was very unlikely that any of this situation could have even slightly damaged the gel coat. Great to hear that one! A scale remover/control could be used for the residue buildup, but it was unlikely to do anything for the rough spots.
At this point, my pool is finally crystal clear which I attribute to a good scrubbing and then ChemGeek's suggestion of using a Slime Bag to help filtration. I still noticed that I still have some white residue coming off on the sides if I rub hard with my finger. But, it's not coming off on the bottom any longer and it doesn't come off by merely touching the sides, so the pool is staying extremely clear. When I get some more time, I'll give it another good scrubbing and let the filter and slime bag take care of it. I don't intend to use scale control. In the meantime, I did add about 180 CH. I do believe I've read on the forum it can help prevent staining. Not sure I'm going to worry about the rougher surfaces. Maybe if I get bored, I'll see if I can affect one area with some fine sandpaper, but even if that worked, I'd have a big job in front of me. The pool is clear and that was my main concern!
I called San Juan today, the pool manufacturer. They said the pool does not need CH. I said that was odd since my owners manual called for a range of 300-350! I asked about what could cause the white residue and the rougher patches of fiberglass. The white residue is often attributed to too much CH in the water, but this was not the case for me. Perhaps for me, the residue was some Alum floc that dried on the pool surfaces when I unsuccessfully tried to floc the pool a few weeks back. The rougher patches were not really explainable other than having a lower/higher than normal range alkalinity for a period of time. But, I do not think I have this issue either given I'm testing Alk once a week.
The remedy for both was to scrub the pool. Using a 1000 grit sand paper was suggested to use on the rougher spots. Given the pool has a 32 mil gelcoat it was very unlikely that any of this situation could have even slightly damaged the gel coat. Great to hear that one! A scale remover/control could be used for the residue buildup, but it was unlikely to do anything for the rough spots.
At this point, my pool is finally crystal clear which I attribute to a good scrubbing and then ChemGeek's suggestion of using a Slime Bag to help filtration. I still noticed that I still have some white residue coming off on the sides if I rub hard with my finger. But, it's not coming off on the bottom any longer and it doesn't come off by merely touching the sides, so the pool is staying extremely clear. When I get some more time, I'll give it another good scrubbing and let the filter and slime bag take care of it. I don't intend to use scale control. In the meantime, I did add about 180 CH. I do believe I've read on the forum it can help prevent staining. Not sure I'm going to worry about the rougher surfaces. Maybe if I get bored, I'll see if I can affect one area with some fine sandpaper, but even if that worked, I'd have a big job in front of me. The pool is clear and that was my main concern!
I have never owned a pool before moving into my current residence. I am having an issue with what I hope is a buildup of calcium and NOT the gel coat coming off my fiberglass pool. When I run my hand along the wall a white milky substance comes off on my hand and for a few seconds makes the water look milky. The walls feel like they have little grains of sand on them, but they are not totally covered with this grit. Maybe the grit has and inch or so in between each piece of grit. Does this sound familiar to anyone?
Here is a possible theory. Would keeping a fiberglass pool on the acidic side have the effect you are all speaking about. I know that keeping the pool slightly acidic also helps keep some of the staining in check and I for one have done just that but over the long haul you have to wonder if it is breaking down the top layer of gel??? Just a though...
fmblizz
fmblizz
We installed a fiberglass pool last year. This is our second pool from this manufacturer and we never had any problems with the last pool, so this is totally new and unexpected for us.
The whole interior of the pool below the water line looks chalky and gives the appearance of being significantly faded/bleached out in comparison to the part that is above the water line--the walls and steps are worse than the bottom. However, the white color does not come off when you rub your fingers on it (as a lot of people earlier in the thread are describing) or even with a nylon scrubber. This makes me think it's not a calcium buildup. My guess is it is either some sort of silica buildup or the gel coat on the pool failed. The pool manufacturer's suggestion is to drain the pool and scrub the whole thing--but he can't guarantee that this would fix the problem or that the problem wouldn't reoccur.
Does anyone have any experience with removing silica deposits? We figured the conservative thing to try was Scaletec, and the literature found online says that it will not work quickly on silica deposits but will work slowly. We are ok with trying this as opposed to spending a lot of money on having the pool professionally scrubbed. I am wondering how the Scaletec has worked for anyone who has used it on silica deposits.
Thanks in advance for any help you can give.
The whole interior of the pool below the water line looks chalky and gives the appearance of being significantly faded/bleached out in comparison to the part that is above the water line--the walls and steps are worse than the bottom. However, the white color does not come off when you rub your fingers on it (as a lot of people earlier in the thread are describing) or even with a nylon scrubber. This makes me think it's not a calcium buildup. My guess is it is either some sort of silica buildup or the gel coat on the pool failed. The pool manufacturer's suggestion is to drain the pool and scrub the whole thing--but he can't guarantee that this would fix the problem or that the problem wouldn't reoccur.
Does anyone have any experience with removing silica deposits? We figured the conservative thing to try was Scaletec, and the literature found online says that it will not work quickly on silica deposits but will work slowly. We are ok with trying this as opposed to spending a lot of money on having the pool professionally scrubbed. I am wondering how the Scaletec has worked for anyone who has used it on silica deposits.
Thanks in advance for any help you can give.
I have a unique situation with the same gel-coat chalky problem. My saltwater pool is 10 years old. 5 years ago we had an issue with bubbles in the gel coat and a few small holes that penetrated the shell. Under our 25 yr warranty, the the manufacturer came out and repaired the affected area (sanded, patched, repainted).
It is only on this repaired area that we are having the chalky problem, no issues with the original fiberglass surface. After a single winter, the patch began to discolor and no longer matched the rest of the pool; it looked dingy and I couldn't get it clean. It also had a bumpy texture unlike the smooth surface of the rest of the pool. After 2-3 years I began to notice it was making our feet & hands white and chalking upon touch (the area was the stairs). 5 years later, the coating has worn through in spots and we can see the yellow fiberglass mat.
I never considered it was a chemical issue, because the original surface was unaffected. My theory was that the gel coat patch product was inferior or applied incorrectly.
Our pool manufacturer has since gone out of business (so much for the 25 year warranty!) and we need to resurface the pool considering that the raw fiberglass is now showing through. Plus, we'd like to make the whole thing blue; it's white now. However, I want to avoid future chalking problems by understanding the issue and choosing a knowledgeable contractor.
Everyone here seems to think it is a scaling/chemical imbalance issue. But, I don't think it is a calcium deposit or scaling issue...unless these things eat the gel coat. My gel coat patch is disintegrating. Is there anyone out there who can give me some advice?
It is only on this repaired area that we are having the chalky problem, no issues with the original fiberglass surface. After a single winter, the patch began to discolor and no longer matched the rest of the pool; it looked dingy and I couldn't get it clean. It also had a bumpy texture unlike the smooth surface of the rest of the pool. After 2-3 years I began to notice it was making our feet & hands white and chalking upon touch (the area was the stairs). 5 years later, the coating has worn through in spots and we can see the yellow fiberglass mat.
I never considered it was a chemical issue, because the original surface was unaffected. My theory was that the gel coat patch product was inferior or applied incorrectly.
Our pool manufacturer has since gone out of business (so much for the 25 year warranty!) and we need to resurface the pool considering that the raw fiberglass is now showing through. Plus, we'd like to make the whole thing blue; it's white now. However, I want to avoid future chalking problems by understanding the issue and choosing a knowledgeable contractor.
Everyone here seems to think it is a scaling/chemical imbalance issue. But, I don't think it is a calcium deposit or scaling issue...unless these things eat the gel coat. My gel coat patch is disintegrating. Is there anyone out there who can give me some advice?
I know this is an old thread but I was having similar problems last year and the pool shop told me to pour muriatic acid on it (on the stair). It instantly cleared up. I forget exactly what caused it but I had to lower the PH quite a bit over several days. I would try it first to see if it is the same issue.
- Jun 22, 2014
- 47,797
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus