Black Algae or metal stains?

[Newbie kate]

We have been battling black areas in our pool. salt water pool, on well water, fill weekly and we have owned it a year so I’m new to pools.
We thought it was black algae but I’m wondering if it’s copper stains. We have quadrupled shocked it twice and scrubbed with wire and chlorine tablets an still have black on walls , and in other spots. Also new white cracks have appeared. Pool was not built properly and appears to not have expansion joint so concrete foundation is pulling away. Other than that I have no problems Thanks for any help!

 

[Texas Splash]

A well would indicate iron. Try rubbing a Vitamin C tablet on a stain to see if that works to confirm.

 

[YippeeSkippy]

You have a vinyl pool, right?? Your signature line says so.....???
Just an FYI- Black algae can not attach to vinyl or fiberglass pools. It may still be regular run-of-the-mill algae, of course.

 

[Newbie kate]

A well would indicate iron. Try rubbing a Vitamin C tablet on a stain to see if that works to confirm.

I will try this again, first time I tried it didn’t do much.

 

[Newbie kate]

You have a vinyl pool, right?? Your signature line says so.....???
Just an FYI- Black algae can not attach to vinyl or fiberglass pools. It may still be regular run-of-the-mill algae, of course.

I don’t anymore, it’s concrete. I’m not sure how to update the signature line.

 

[mknauss]

I don’t anymore, it’s concrete. I’m not sure how to update the signature line.

Create Your Signature - Further Reading

www.troublefreepool.com

 

[Aksneed188]

Thread 'Dark spots in plaster'
Dark spots in plaster

It was winter so I didn’t get in to check it. Ended up being bad plaster job.

 

[reggiehammond]

Cracks in the deck and visible cracks in the pool are very concerning, to my eye.

 

[Newbie kate]

Thread 'Dark spots in plaster'
Dark spots in plaster

It was winter so I didn’t get in to check it. Ended up being bad plaster job.

So the black areas were a bad plaster job? I was wondering about that. So you had to replaster?

 

[Aksneed188]

Not yet. I’m ok with it for now. It seems only color is the problem

 

[Aksneed188]

Not yet. I’m ok with it for now. It seems only color is the problem

It’s slowly taking over whole pool