Stains from roofing nails

Mar 17, 2021
18
Charlotte, NC
Pool Size
13000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
Hi all!
I have rust stains from roofing nails on the floor of my plaster pool.
I began the ascorbic acid treatment this morning after bringing the FC to 0 and adding algaecide. I added 1 pound of ascorbic acid about 10 hours ago and there has been zero improvement!
Help!!

PS: My pool is 15x 30, with a tanning ledge, deepend is 6 feet. I’m not 100% sure the volume but from what I read the guidance is 1/2 to 1 pound per 10000 gallons so I figured a whole pound wouldn’t hurt and wouldn’t be too little

(Feel free to move this to the proper forum if I opened it in the wrong spot)
 
Did you confirm the stains lift with some Vitamin C paste before beginning the AA treatment?
 
Where did you get the ascorbic acid from?
 
From Ascorbic Acid Treatment - Further Reading

Another alternative is oxalic acid, but one has to be careful to not overdose or use it in high CH conditions due to the precipitation of calcium oxalate (i.e. it's OK as a local spot treatment, but not so good for a broad amount -- probably no more than 1 ounce per 10,000 gallons). Oxalic acid has a higher toxicity profile (so just be careful not to get it on your hands or inhale dust) though it's still less hazardous than some other chemicals we use for the pool.
 
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.