Stains in Fiberglass pool

[BarryY]

OK, I just ordered some. Can't wait to try it, thanks.

[mbar]

I also have a fiberglass pool, and I have learned to deal with the stains pretty effectively. When I get stains I use ascorbic acid, and a metal free product. The cloudy water is the metal free agent combining with the metal that has come back into solution. If you have a lot of metal in solution and the water is cloudy, you should not start to bring up your chlorine until the water is cleared - you can put a chlorine puck in the basket so the metals will stain the filter. You have to try and keep the ph around 7.2, not higher - it is hard to keep the ph there, because the stain treatment brings down the ph, plus the puck in the skimmer will add to lower ph. Be sure to keep your filter running 24/7 - once the water is clear, you can start to bring up the chlorine. I use regular bleach, and I don't run high chlorine levels - it isn't necessary especially if you keep your cya under 50. In my opinion, fiberglass pools tend to stain, I now treat it heavily at the beginning of the season with a metal free product, and keep the filter running 24/7 when I have high chlorine levels. All water and pools are different - you will have to experiment with yours to see where you need to keep your chlorine & ph to keep the stains away. Don't worry so much - if it stains, it can be taken care of!

[Arizonaoldman]

I too have a 21,000 gallon fiberglass pool and a salt to chlorine generator. We have extreamly hard water and I just had my generating cell replaced after only two years. (free of course) Last year I began to have brownish 'build-up" at, or above the water line only in two areas (both wind driven areas) I had been using a 'Bio Guard" product "Off the Wall" on a weekly basis until late last fall. This year the stains are quite noticeable and no amount of "Off the Wall" and/or elbow grease seems sufficient. Do you think the Ascorbic Acid trick will work for me? Remember that most of the stain is above the water line. Will scrubbing with the ascorbic acid do the trick.

By the way I life in north western Arizona.

Ralph

[mbar]

If the stain is above the water line, then I don't know how it would be from iron falling out of the water. You can tell if it is mineral by rubbing a vitamin c tablet on the stain. If it takes it off, then ascorbic acid would work. You wouldn't have to scrub with ascorbic acid - just letting it touch the stain will make it disappear. Let me know if the vitamin C tablet (you can put a couple in a sock, soak the sock and rub it on the stain) works. If it is stain from leaves, they come off after chlorine is on them for a while. I have also had good luck with cleaning the water line with magic erasers. Hope this helps

[Arizonaoldman]

I tried the Vitamin C Tablet today. Got it wet then used it directly on the stain.
No luck whatsoever. Tried Mr. Clean Magic Eraser yesterday, still no luck. I refuse to give up.

Ralph

[mbar]

I read somewhere that you can put a little ph reducer in a sock, wet it, and rub it on the stain - if it is mineral it should take the stain off. You probably would want to wear gloves when doing this. Let me know if this helps. I wouldn't give up either!

[DavidD]

You are in good hands Ralph. Marie (mbar) helped me allot a couple of years ago and turned me on to the Vitamin C. I owe her much gratitude. I too have a Fiberglass pool and seam to have to treat my pool a couple of times each season. On another thread, waterbear has brought to light a yet unsubstantiated claim by a company (Water Tech I believe?) that a lack of calcium could cause problems in vinyl/fiberglass pools. No one is sure if this is true yet and I personally have my doubts but just for the sake of "research", would you post your numbers? Mine are as follows:

FC 3
CC 0
TC 0
PH 7.5
ALK 80
CH 60
CYA <30
Temp 84
16,000 gallon I/G Fiberglass

I currently have stains. My stains generally appear as grey lines running from one side of the pool to the other. They even appear as orange/yellow sometimes in certain light. The pool has been open for a couple of weeks now and the stains have progressively gotten worse. The last treatment was in August '05 and I'll be giving it the ascorbic treatment after the weekend. I'm trying to keep a log to try to figure out what is causing these stains and would like to compare others numbers when staining has occurred. I use a water filter (cheap RV type) when filling and have had my water tested for metals and there are no traces of Iron or Copper. Notice My Alk and CH are low? I'll be working on those after the treatment next week. I usually keep ALK between 90 & 100 and have never worried about CH but it has never been this low. I did do a partial drain when opening to get the CYA down and I guess the filter is working since no calcium seems to be added. Thanks in advance for your help.

Dave