Fiberglass pool badly stained

[DavidD]

hoogie,

I have a 16k gallon fiberglass pool. I have never drained it completely since the manufacturer told me not to as it will void the lifetime structural warranty. While building the pool, this concerned me so much I kept inquired about draining further. I found out fiberglass pools can in fact be drained if:
1. There isn’t any ground water under the pool. Mine has an access lid (identical to the skimmer) with a 12” plastic pipe that extends to the bottom of the deep end. Builder said this was for pumping out/inspecting ground water in case the pool needed to be drained.
2. The walls MUST be braced. One of the workers told me they use “spacer jacks” like the ones used in the back of a tractor trailer to brace loads. I’m not exactly sure how often/how many braces must be used. This is apparently to prevent stress on the walls from the settling ground around the pool.

As duraleigh suggested, I’d get a manufactures advice. Keep pressing them. If the original is no help, try C&W pools in Joelton, TN (615) 256-7329. They have been making fiberglass pools for 40+ years. I’m sure they'll tell you don’t do it but it may be worth a try.

Have you tried using ascorbic acid? It has worked wonders for me in the past. It is available several ways. I generally use a product called Stain Free however I have noticed several other products out there. Anything that says ascorbic acid (a.k.a. vitam C) should do the trick. It is around $40 for a dosage that treats my $16k gallons and I get it at the local pool store. I end up treating once a season to remove metal stains. Definitely try this before you drain your pool. I found out about it here on the forum after spending $100 on Jack’s Crap to no avail. It worked perfectly on the first treatment. Good luck.

[hoogie]

Thanks David, I'll check into that. It would be mint if I didn't have to drain it.

Mark

[Hawksnestbay]

http://www.chemistrystore.com/Ascorbic_Acid.htm

The difference between food grade and not is that when they get it in the box form from the manufacturer it is food grade. Once they re-package it in smaller quantities, it can't be sold as food grade. I found this out because last summer they ran out of the non-foodgrade containers, and he called me to ask if I would take the bigger box.

It is the exact same product as the pool store "Ascorbix" and the like and much cheaper. However, Acorbic acid does not fix your problem, it only helps you return the stain to "a solution". A sequestering agent, which you will have to buy at the Pool Store will "hold it there".

Read the Pool Docs Thread regarding Metals and Staining. All pools are different. And I have not found one pool store or pool maintenance company here in Southeastern Mass. that even remotely understands the concepts of this Forum.

I have a 35,000 gallon vinyl lined pool with a heater.My metal comes from my fill water, which is a well. The fill water has a very low PH {5.5}and High Mangenese. I have a very hard time maintaining the PH at 7.0 in my pool.
I chlorinate my pool with nothing but sodium hydro chloride, using a liquimate feeder in a 5 gallon gerry can, and 1/2 to 1 gallon of 12.5 per night.
I never allow my stabilizer level to go over 40.
Filter is 6 hours on, 6 hours off. The liquimate adds just enough SHC to keep me chlorinated . This formula keeps me stain free until the squestering agent wears off, or my ph rises to 7.4, at which point the metal falls of solution and stains my liner. Then I add the acorbic acid, it magically disappears, and the circle remains unbroken.

Good luck to pool owners with wells.