Black Stains Fibreglass

denniswiseman

Bronze Supporter
Nov 27, 2014
235
United Kingdom
Another tester just had success on copper stains that had turned black using muriatic acid with the tool I will link below...this is likely only a suitable approach for plaster...and would still require some metal sequestrant, i suspect...

Not especially cheap, but it seemed to work well for him:
Amazon.com: Purity Pool UAW Underwater Acid Wash Set: Patio, Lawn Garden

(Since the MA worked on it.)
I have been looking to get this kit but there doesn't appear to be anywhere outside the USA to get it
I have seen it on Ebay for about $140 when everywhere else is about $70 but they don't ship to the UK
Does any one have knowledge of a retailer over there that can or will ship here
 

frustratedpoolmom

TFP Expert
LifeTime Supporter
In The Industry
May 20, 2007
12,250
Key West, FL
That looks like metal staining, most likely copper. It is not black algae, BA doesn't look like that.

Copper can enter the pool a number of ways. If normal water replacement doesn't happen, over time the level can build and cause staining like yours, especially in older fiberglass if the CH hasn't been maintained to protect the surface. I would not recommend a SS brush on fiberglass, only plaster pools.

You may have a very hard time removing the staining... somewhere from years ago there is a post about removing copper stains...I'll see if I can find it. In the mean time if you have the powder "ph down" put some in a sock, find a weigh to weigh it down and set it on one of the stained areas, leave it there for a bit and report any changes.
 
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denniswiseman

Bronze Supporter
Nov 27, 2014
235
United Kingdom
In the mean time if you have the powder "ph down" put some in a sock, find a weigh to weigh it down and set it on one of the stained areas, leave it there for a bit and report any changes.
I have some PH Down from when I used to balance the pool water with it
I'm slightly incapacitated at the moment for it may have to wait a few days
BTW Most of my staining is on the side
 

pabeader

LifeTime Supporter
TFP Guide
May 14, 2015
4,349
Cartersville Ga
No need to order, you can get it at local druggist. It's the stuff you take to stop a cold. Just get the plain stuff and crush it up in a sock. Hold it on the stain. If it's like mine it will be like a magic act.
 

denniswiseman

Bronze Supporter
Nov 27, 2014
235
United Kingdom
I don't see where you mentioned trying the vitamin C. I had black stains on my pool and that cleaned them right up. Sure couldn't hurt.
The ascorbic acid works a treat. I rubbed the stains and the stain quickly disappeared


In the mean time if you have the powder "ph down" put some in a sock, find a weigh to weigh it down and set it on one of the stained areas, leave it there for a bit and report any changes.
The PH down worked as well but not as fast as the ascorbic acid.
What is the next step as most of the staining is on the side?
 

pooldv

TFP Expert
Platinum Supporter
LifeTime Supporter
Moderator Emeritus
Aug 10, 2012
25,412
FL panhandle
Yes and I checked it out. The supplier is from the States. The postage and delivery gives it away and when I checked they were in Texas
What?!? Maybe I linked the wrong one. The one I was looking at even had a note that said shipping to the US is not available. What the heck?
 

pooldv

TFP Expert
Platinum Supporter
LifeTime Supporter
Moderator Emeritus
Aug 10, 2012
25,412
FL panhandle
Here, this one
Jack Outdoors amazon.uk

Jack's Magic JMPINK032 Pink Stuff Metal Solution

by*Jack's Magic

Be the first to review this item

*

Price:£19.94*

In stock.

Sorry, this Seller doesn’t deliver to the*United States*Learn more

Dispatched from and sold by*Below Cost Products UK.