What is this???? Please

[ravengotu]

We have tried alage remover, for black algae and so far nothing is happening.

Is this maybe just a stain of the concrete?

Any thoughts or suggestions please...Thanks so much

 

[duraleigh]

Might be calcium scale...certainly not sure. We are only guessing wildly.

If you can post a set of test results, that will be very helpful.

 

[ravengotu]

Okay got the resluts..Hope I did this correctly

CL=5
BR=10
FC=10
CC=1
TC=11

CH=425
TA=50
CYA=90

Thanks for helping me out with this

 

[YippeeSkippy]

You have a chlorine pool I take it? So ignore the Bromine side of the block.

Have a pH to share with us?

Do you put any algaecides or metal containing products in the pool?

 

[ravengotu]

Okay sorry, cant read my chicken scratch...

PH=6.8

I just recently put an alage fighting thing in as thought it was black algae..Now I know it is looking like lack of calcium pitting


Thanks again for the help all

 

[JamesW]

Looks like extensive copper staining. The turquoise is one form of copper; the gray and black are another copper compound.

 

[ravengotu]

Any suggestions to clean this up. I mean it is clean water but just so unsightly.

Thanks

 

[JamesW]

Copper staining that bad is not easy to clean.
How old is the plaster?
What is the original color of the plaster?
Try scraping off the top layer with a wood chisel to see what the plaster looks like under the staining. Don’t gouge the plaster. Just do a nice, clean, thin scrape. It will leave a mark, so don’t do it anywhere a mark will look bad.