Help with scaling on spillover

drewhiggs

Silver Supporter
Jul 9, 2017
74
Georgetown, TX
#1
Would someone be able to help determine what type of scaling this is and how to keep it at bay? This is a new install that was finished the middle of December and is only happening on the spillover. The way the pool is plumbed, it is always spilling over when the pump is in pool mode.

Pool test
Fc: 5
Cc: 0
Cya: 40
Ta: 70
pH: 7.7
Ch: 250
5C9ECE08-706F-4F6F-8A78-B6C0F9983582.jpeg
 

JamesW

TFP Expert
Mar 2, 2011
12,822
#2
Whenever you have water that starts and stops, you can get scale from minerals in the water when the water evaporates when the fountain is turned off.

That might be part of the issue.

I suspect that there is also some efflorescence where water from the spa is bleeding through the wall and dissolving the minerals from the wall and depositing them on the wall.
 

Jimrahbe

Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
10,508
Bedford, TX
#3
Drew,

Another issue is that it appears to me the water is wrapping around the spillover stone and traveling back and then down the stacked stone..

The bottom of the spillover stone is supposed to have a groove in the bottom that stops that from happening. The groove should be about 1/4" back from the front and about 1/4" wide and 1/4" deep..

Surface tension holds the water to the bottom of the stone.. the groove stops it.

Thanks,

Jim R.
 

drewhiggs

Silver Supporter
Jul 9, 2017
74
Georgetown, TX
#4
Any way to remove the mineral buildup?

It definitely travels back to the stone behind the lip when I have the pump running at low speeds. The groove in the stone makes sense, but no easy way to do that now that’s it’s installed.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,492
Tucson, AZ
#5
Why does the spillover operate during POOL mode? Is there a return in the spa connected to the pool side of the return plumbing? Can you valve it off?

ScreenLogic and the ET panel give you optional controls for water features. I added an additional valve actuator to my spa make-up return line to automate my spillover. Despite conventional PB “wisdom”, a spa does NOT need to spillover all the time. Even in the hottest parts of my summer, I only activate my spillover for maybe 90mins per day.
 

drewhiggs

Silver Supporter
Jul 9, 2017
74
Georgetown, TX
#6
I have 2 returns going to the spa that I can shut off manually to stop the spillover. Is it difficult to install an actuator? It would be nice to turn off the spillover when I run the pump at low RPM’s.

I’ll do a forum search to see if anyone else has had any luck removing these mineral stains.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,492
Tucson, AZ
#7
You could try a pumice stone and lightly rub the stained areas. Excessive calcium scale would need to be blasted off using either glass bead blasting or kierserite media. I would avoid acid treatments as that could damage or discolor the stone.