Yellow stains on fiberglass

[LivingTheDream]

Please start your own thread Thanks, Butterfly
Split from here: post489020.html#p489020

Hello, new here also. And having the same problem on our fiberglass pool. The vitamin C tab does remove the stain, but brushing and rubbing the stain with organic cleaner does nothing. The pool store that tested the water said that there is NO metals in my water. So what is causing the stain? I have a 6 inch deep ring around the entire pool, probably the winter water line, and some tiny rust spots on the princess deck. Should I treat it like a metal stain and add ascorbic acid since the Vitamin C works?

Pool Test:
FAC = 3.7
TC = 3.86
CC = 0.16
PH = 8 (have added PH decreaser since this test)
TA = 143 (but just raised it)
Cal Hard = 208
Cyanuric Acid = 32
SALT = 3000
Saturation Index = 0.7
All of the 6 metals/phosphates read 0

Pool is an 15 x 30 IG Fiberglass, 11,000 gal, with heater and Salt Water Chlorinator

 

[duraleigh]

Welcome to the forum. :lol:

Should I treat it like a metal stain and add ascorbic acid since the Vitamin C works?

Yes, definitely.

 

[Butterfly]

We have instructions in Pool School for doing an Ascorbic Acid Treatment.

If you have a small amount of staining, you could crush Vitamin C tabs in a sock and move it around on the stain. Large amount of staining would likely need the complete AA treatment.


Welcome to the forum