Brown Spots on Plaster - 1 Year Old Pool

[pigskintd]

I just got back from a 10 day vacation and came back to these brown spots all over the pool, but mainly on the sun shelf. A pool brush didn’t seem to do anything, but when rubbing with my nail it removed some of the brown spreading part but not completely.

Is this due a chemistry issue? I have been dealing with high PH for awhile which I think is scaling my filter. The filter jumps to high pressure within an hour of cleaning. I thought the filter issue might be an algae issue, and was planning to do a chlorine drop test (CC is 0-0.5).

Could this be due to high PH or algae? Or is it something wrong with the plaster? I would appreciate helping identify the issue and how to fix it. I have been using TFP since we built a year ago, you guys are always great. Thanks for the help in advance!

FC - 6.0
CC - 0-0.5
CYA - 70
PH - 8.2
CH - 450
TA - 80
Salt - 3400

 

[cdadams1223]

Have you added anything to your pool besides the occasional LC, muriatic acid, etc.? I do see that your pH is higher than it should be. What is your CSI currently?

 

[Oly]

Do you use a yard service? Any chance these are fertilizer pellet stains, perhaps iron? Stains in Your Pool

 

[pigskintd]

I have only ever added pool salt, acid, and CYA via the sock method. I have been battling high PH since we built the pool. I think the main cause is they didn’t wire my AquaLink properly so the hot tub is always on overflow. I was fine for 10 days so no acid was added and accidentally left the sun shelf bubblers on.

CSI shows 0.56. This has been a common issue for me which is why I think the filter is scaled up.

 

[pigskintd]

Do you use a yard service? Any chance these are fertilizer pellet stains, perhaps iron? Stains in Your Pool

I just hired a lawn service who did blow grass over my fence. Doubt fertilizer could have gotten in the pool because it would have had to go over the fence. The entire backyard is fake grass.

 

[Oly]

Perhaps organic material staining?
Try the stain removal tests listed in the link from my previous post for organic material and iron.

 

[pigskintd]

Perhaps organic material staining?
Try the stain removal tests listed in the link from my previous post for organic material and iron.

The pool has been dirty, so maybe it’s organic material. I don’t have any trichlor pucks to test tonight.

 

[pigskintd]

Perhaps organic material staining?
Try the stain removal tests listed in the link from my previous post for organic material and iron.

The Trichlor puck didn’t do anything. For the Vitamin C test, can I just use an EmergenC powder pack that you normally drink and put that in a sock? Or will it dissolve too quick?

 

[Oly]

Best to find some 100% generic ascorbic acid, vitamin C pills, white. No dyes or other metals.