Splotchy brown discoloration at floor of champagne spa

[jmcmd1980]

I noticed recently, some splotchy brownish discoloration at the base of my champagne spa. As far as I can tell, my water has been balanced, though I did let the pH rise to around 7.8 during the cold weather months in Florida. This gave me a CSI near zero but I’m concerned. I’m seeing scaling though there was no Brown in the remainder of the pool.
Current numbers:

Ph 7.8
FC 7
CC 0
TA 80
TH 300
CYA 60
Salt 3200
Borates ~ 35

My pool is still under warranty, so I called the pool company who came out today and said I was keeping the pH too high and the brown on the floor was scale and they also felt the outside walls of the champagne spa were rough from scale. He also suggested I change the filter, felt the pressure was too high when running full RPM at 3450.

I lowered the pH to 7.4, hoping to see the brownish fade.

Any suggestions greatly appreciated

Jim

 

[mknauss]

Get some vitamin C tablets. Put in a thin sock and crush them a bit. Set on the stain for a few minutes.

 

[jmcmd1980]

Thanks! Anything else you can see that I’m doing wrong?

 

[mknauss]

No. Very improbable that the water is creating scale.

 

[jmcmd1980]

Thanks, I’m very mistrustful of what the builder has told me since the build completed, and I began managing the pool myself because of these discrepancies and cost of “professional “ pool management. I very much appreciate the expert help from this forum.

Jim

 

[jmcmd1980]

I did the vitamin C treatment and it seemed to fade things but not completely. I also adjusted my automation to apply more water exchange and flow to the champagne spa. Do you think there’s any place for a sequester like Jack’s purple

Jim

 

[mknauss]

If the vitamin C faded the color of the stain it is likely iron.

 

[jmcmd1980]

I bought some test strips for copper and iron in both read zero. I brought a sample to the pool store and they also tested zero iron and zero copper. Is there any place for the purple sequestrate?

 

[mknauss]

Iron is on the surface, not the water.
No need for a sequestrant. I would treat the spa separately with ascorbic acid and then drain the spa volume when the stain is lifted. Do not mix the water with the pool water during this.

 

[jmcmd1980]

Iron is on the surface, not the water.
No need for a sequestrant. I would treat the spa separately with ascorbic acid and then drain the spa volume when the stain is lifted. Do not mix the water with the pool water during this.

Thanks, I will give it a try, it’ll probably take some time for things to fade completely. Thanks for the expert advice and continued help.

 

[mknauss]

Once you get enough ascorbic acid in the water (follow Ascorbic Acid Treatment - Further Reading) the stain will lift quickly.

 

[jmcmd1980]

Thanks, I will give it a try, it’ll probably take some time for things to fade completely. Thanks for the expert advice and continued help.

Will do, it’s interesting that the Brown is only in the champagne spa not the rest of the pool as far as I can see.

 

[mknauss]

It is odd, but it is shallower, less water, etc. So you likely can see it better. Water temperature can effect things also.

 

[jmcmd1980]

Where do I obtain the ascorbic acid? Just crush vitamin C tablets, buy it commercially, any dose recommendation for a 400 - 500 gal champagne spa/

Thanks so much. Jim

 

[jmcmd1980]

I just saw the link to purchase bulk ascorbic acid online. I ? need to treat the whole pool with sequestrant, not just the spa with no spillover or makeup valve open?

Jim