White scale in fiberglass pool

[fleetz54]

I have a 2 and 1/2 year old fibreglass pool which has a white scale when it dries. When wet it is hard to see. If I drop the pool level a solid white deposit is seen when the water dries.

This may or may not be a coincidence but it appeared after I put a Sparkle Pill in the pool a day ago. Ran the pump per the instructions, it went in at around 2pm and when I got up the following morning I noticed a white 15mm (nout 3/4") mark just above the pool line. Thought it would just wash off with a dense sponge but no joy. The Sparkle Pill contained Alumina Salt which is a floculate.

I contacted the manufacturer of the Sparkle Pill who basically said that no way would the pill cause the issue! It wasn't there before I put it in and no other chemicals were put in. So I have just assumed it has something to do with the Sparkle pill.

I then proceeded to use on a test section some Bi Carb of Soda no joy, then tried car cut and polish no joy what so ever when the section dried the white deposit showed as before. The fibreglass gel surface from the water line down feels course not smooth as is the case above the water line.

Anyway I got our local pool shop guy around and he tested the water as his thinking was a high level of calcium, results were vitually no calcium detected and the Ph was low but all agreed that it would cause this issue. A couple of handfulls of Ph buffer and the pool is in perfect balance. On close eximination with the pump switched off and pool perfectly still if you look down the sides you can just see a slightly uneven deposit of something on the walls. When the deposit is wet it is hard to see .....when it dries it is white and very prominant.

I then proceeded to use on a test section Bi Carb of Soda, car cut and polish no joy what so ever when the section dried the white deposit showed as before. At this stage I rang our local pool shop for assistance.

The pool shop guy has hit a test patch with everything he had. Multi stain remover, some other stain removers and after consultation with the pool manufacturer we tried at his suggestions some citric acid (no joy) then 50/50 Hydrochloric Acid/water (no joy) then fully concentrated Hydrochloric Acid and still no joy. Nothing used reduced or removed the deposit.

I have read here and in other forums that metals can be attracted to fibreglass pools. Unfortunately the description

For the moment I have the water about 50mm above the water line ensuring that the deposit remains wet and I don't have extended periods where the deposits remain dry on the fibreglass.

We still are not sure what the deposit is, obviously if that was known then the corrective action is probably the easy part. I am hoping that some one might have some suggestions as to what it might be and what might a solution to correcting the problem. I would appreciate any thoughts, comments and suggestions.

Regards,

Paul

 

[frustratedpoolmom]

Re: White scale in fibreglass pool

Welcome to TFP...

Can you provide a bit more info regarding your details...
Where are you located?
and

Please post a full set of test results:
FC
CC
PH
TA
CH
CYA

By providing us with a full set of results, we can advise you better.

 

[fleetz54]

Re: White scale in fibreglass pool

Thanks for the reply.

I will see if I can get the info from the pool shop guy and post it.

REgards,

Paul

Welcome to TFP...

Can you provide a bit more info regarding your details...
Where are you located?
and

Please post a full set of test results:
FC
CC
PH
TA
CH
CYA

By providing us with a full set of results, we can advise you better.

 

[fleetz54]

Re: White scale in fibreglass pool

Hi,

An update. No progress so far, what I didn't realise at the time of the first post was the scale is not limited to the top 15mm indeed it is the whole pool. As you drop the water and the fibreglass dries you see the white scale. You can feel it below the water line rough compated to the fibreglas above. Also if the pump is off and water still and you look down the walls of the pool you can just see something sitting on the surface.

The water at the time of testing showed no abnormality. Virtualyl no calcium which was the original suspect. THe pH was a little low but all else was well. Sorry I can't give you all the readings you were after. I have attached a couple of photos which hopefully give folk a clue.

The pool has had Lo Chlor Metal Solution applied in concentrated form and also a week with the prescribed amount for the size of the pool. The corner shot photo is where all the chemicals applied to date has been the test patch area. Here is the info on the Metal solution Lo Chlor Metal solution.

Same with this product Lo Chlor Multistain didn't look at it in concentrated form

Same with this product Lo Chlor Stainaway didn't look at it in concentrated form

I am currently letting the chlorine level drop before putting in Lo Chlor Spotaway and letting that run in the pool for a week. It is a Sodium Metabisulphate based chemical, not sure that over confident that this will have any postive effect. Got to give it a try.

Lo Chlor technical people are currently suggesting the way forward .....unfortunately progress is zero.

I have spoken to the pool manufacturer and they have never heard or seen this effect. They reassure me that with teh Aquagel coating it can be cut and polished up, the thought of having to do this with a 9 X 4 metre pool does't bare thinking about.

Trust me to be the only person on the planet with this problem

Any thoughts would be appreciated.

Regards,

Fleetz54

 

[JasonLion]

Re: White scale in fibreglass pool

When trying to solve a problem like this one, it is really critical to have a full set of water test results. Scale lines like that are fairly common with certain chemical imbalances, but without knowing your numbers we can't recommend the correct treatment.

Stainaway looks like the most likely chemical to help, but even if it works, it won't solve the underlying problem. The white band will just come back again later.

 

[fleetz54]

Re: White scale in fibreglass pool

It is not a white band as such. As I stated earlier if I drop the pool level where ever it is dropped to the white scale exists. Intially I thought it was just a band up the top but it is the surface of the whole pool.

We have tried Stainaway in in most concentrated form and had no effect on a test patch. I realise that over time Stainaway in the water applied to the manufacturers application might have a different effect. One would expect a concentrated application to show positive signs.....it didn't. Would you still think that Stainaway in it's diluted form would still work? It would be 1 litre in 50,000 with it's recommended initial application.

Our local pool shop came around when the problem appeared and did water sample tests with one of those multi colour dips stick tests. The only thing that was out of balance was pH and was lower than it should be. Everything else was within range of normal. Calcium was virtually nil.

I have looked into seeing if I can get the water analysed more scientifically and can't seem to find a company that does that here. I agree knowing the problem is important. I have even looked at trying to find a company that would analyse the scale by scraping a small sample from the dried scale with a scalpal but again can find a company that offers the service.

I am happy to buy a analyser to provide the measured results, I just want the pool returned back to good condition. What tools are you folks using to get the water sample results you are referring to here??

Again appreciate the feedback and suggestions

 

[DBfan187]

Re: White scale in fibreglass pool

I'd be looking for a new pool service company if they came to my pool and started testing with strips.

 

[fleetz54]

Re: White scale in fibreglass pool

I'd be looking for a new pool service company if they came to my pool and started testing with strips.

Thanks for the feedback. What type of testing tools are you suggesting are available and should be used?? If I can find the source of these then I might be able to contact the distributor and send a sample to one they have supplied a system to.

Regards,

Fleetz54

 

[Bama Rambler]

Re: White scale in fibreglass pool

You've been asked twice for a complete set of test results. There's a reason for that! You'd be surprised what a good set of results will tell us. You don't need to send a sample of the scale off. There's a high probability that the numbers will tell us where the scale is coming from. Then we'll know what to tell you to do to fix it.

The best thing you can do is order a good test kit. There's a comparison of them in Pool School. Then you can provide us with the results we need.

 

[fleetz54]

Re: White scale in fibreglass pool

My local pool guy was able to provide the results you are after. He has been very helpful and is trying everything at his disposal.

FC 0.0 ppm
CC 0.0 ppm
PH 7.4
TA 60
CH 200
CYA 0

The clorinator has been switched off for the last three days to remove the clorine level in readiness for putting in the Spotaway product http://www.lo-chlor.com.au/remprev_spotaway.php this went in today 4kg into 50,000 litre per the manufacturers recommendation.

I should mention that the chlorine levels were in the normal range when we did the intial tests.

Be interested in your thoughts.

Regards,

Fleetz54

 

[Roxy]

Re: White scale in fibreglass pool

Hey Fleetz54, did you ever manage to resolve your pool problem?

I have a 12 Month old fibreglass pool that has developed EXACTLY the same white scale problem as you described. Ive tried every nasty chemical I could lay my hands on, but no joy at all.

Starting to get desparate....

Cheers

Roxy

 

[fleetz54]

Re: White scale in fibreglass pool

Hi Roxy,

Apologies for the tardy reply.

No I have not resolved this issue yet. I am about to apply a product called D-Scale and will let you know if it produces results.

It takes about 10- 12 days to do it's business and I am currently just checking with the manufacturer what the water condition needs to be before applying. So it will take about three weeks to get some feedback happening.

Regards,

Fleetz54

 

[PoolGuyNJ]

Re: White scale in fibreglass pool

You might try using a wide, steel, putty knife to gently scrape the buildup off. It took 7 guys a couple hours to do this to a shell that had had a bad bond and the shell had developed a charge that attracted the calcium. The boss was amazed that it worked as this customer had been difficult and was now ecstatic, bought pizza and beer.

Be careful in the corners.

Scott

 

[fleetz54]

Re: White scale in fibreglass pool

I have also used on a test patch 1200 grit wet and dry and it took two good goes to get the scale off and I mean probably a total of 5 minutes over the two sessions to get back into the gel coating.

I will get a steel putty knife an give a section a try however in my particular case I would not be overly confident this will work. But worth a try.

Regards.

Paul

You might try using a wide, steel, putty knife to gently scrape the buildup off. It took 7 guys a couple hours to do this to a shell that had had a bad bond and the shell had developed a charge that attracted the calcium. The boss was amazed that it worked as this customer had been difficult and was now ecstatic, bought pizza and beer.

Be careful in the corners.

Scott

 

[Roxy]

Re: White scale in fibreglass pool

On a small section I also successfully removed some with 2000 grit wetpaper, and brasso worked as well (and I'm guessing a mild cutting/polishing compound would work too). I haven't tried scraping, as in my case the offending material doesn't seem to be raised very much at all. That, and a fear of scratching the surface.

Apart from those small tests I haven't done anything else - my scale line is about 5cm below my 'normal' water line, and is thus mostly not very visible (until the pool water level drops, and the fibreglass dries out). I guess in my case whatever triggered the precipitate happened when the pool was low, as it doesn't seem to be getting any worse, although the white coating does seem to be more extensive that just the waterline - extending down to the floor, but I haven't drained the pool enough to confirm that.

Fleetz 54, I'd be keen to hear how the D-Scale works out, either way.

 

[fleetz54]

Re: White scale in fibreglass pool

Hi Roxy,

Will do.

I spoke with the chemist of the pool chemical manufacturer of the D-Scale to check what water condition the pool needs to be in before I apply the chemicals. Probably in 4-6 weeks time so it will be a while before I can report back. But report back I will.

Regards,

Paul

On a small section I also successfully removed some with 2000 grit wetpaper, and brasso worked as well (and I'm guessing a mild cutting/polishing compound would work too). I haven't tried scraping, as in my case the offending material doesn't seem to be raised very much at all. That, and a fear of scratching the surface.

Apart from those small tests I haven't done anything else - my scale line is about 5cm below my 'normal' water line, and is thus mostly not very visible (until the pool water level drops, and the fibreglass dries out). I guess in my case whatever triggered the precipitate happened when the pool was low, as it doesn't seem to be getting any worse, although the white coating does seem to be more extensive that just the waterline - extending down to the floor, but I haven't drained the pool enough to confirm that.

Fleetz 54, I'd be keen to hear how the D-Scale works out, either way.

 

[danielb]

Re: White scale in fibreglass pool

Hi fleetz54, Roxy

I wondered if either of you had found a solution or explanation to the problem as I have exactly the same thing, a completely white pool below the waterline that you only really notice when the water level drops a bit. I too have tried most of the stuff you mentioned above before deciding it's not a calcium or scale problem, the hydrochloric acid generated no reaction at all.

I'm starting to wonder if the problem is not a build up or coating on top of the gel coat but something that has affected the very top surface of the gel coat itself, effectively stripping the colour from it. The only way we have successfully removed the white is with fine wet&dry paper and I wonder if we are actually sanding off a fine layer of the gel coat itself - I'm kind of guessing here though!

Any advice or information on how (if) you resolved this would be great. Our pool is chlorine based and, if I'm honest, we probably run the chlorine a little high (4-5) and the PH a little low (7.0). All levels are fine now although I can't remember how things were when this problem occurred around a year ago.

Many thanks

DanielB

 

[skijunkie]

Re: White scale in fibreglass pool

You guys should maybe start trading information on the manufacturer and build dates of your fiberglass shells. Maybe it has nothing to do with the water chemistry and is instead a defect in the gel coat from a particular manufacturer. It could even be a particular batch or process they were using when you guys bought your pools.

Just a thought, hope you guys find a cure.

 

[fleetz54]

Re: White scale in fibreglass pool

Hi Folks,

Sorry for the delay in replying to your post.

I still have not applied D-Scale we have had a long and very protracted wet season which has only recently broken. There was no point applying D-Scale with rain we have been having. I have also have just returned from a month in Australia. I will drop the chlorine level in the next day or so and put the prescribed amount of D-Scale in and report back in 2 weeks time.

Let's see what this D-Scale does. In touch in a couple of weeks.

Regards,

Paul

 

[Guest]

Re: White scale in fibreglass pool

Have the same problem but much worse with a 2 year old pool. Started from day one after the concrete surface was poured there started to be white vertical streaks after it rained noticable on the surface above the pool water line. Thought that when the tile was installed no problem cause that would cover that up. Now the whole surface of the pool is white when drained and has caused the color to change of the pool when water is in it. Our fiberglass pool is a black color, now when drained totally white. The mfg. has done some test patches buffing with a compound which has helped to remove the white but it is still cloudy and not the finish it was originally when installed. They have said what difference does it make if the pool when drained in white, but with water in it is somewhat the color it should be? We would like to make some sense of this afterall we went with a fiberglass pool because after research we felt it was superior to gunite however with these problem we feel we have made a terrible mistake that is not correctable, are totally unhappy with this pool, and may have to rip it out and start over. Any help would be much appreciated. Also we have a salt cell chlorinator and test the water chemistry regularly.