SWCG Buildup

joshf · May 21, 2022

I've read enough here to know that calcium can build up on a SWCG, but I'm surprised to see it already - I installed mine about 5 weeks ago.
I keep my levels (mostly) within the Pool Math ideal ranges - TA is a little high (90), and pH seems to be constantly rising, so may be reaching 8 for a day before I catch it. Surprised how much muriatic acid I have to keep adding - I was hoping the SWCG would mean less maintenance.

I'm curious if this level of buildup is cause for alarm for a 5 week old cell.

joshf · May 21, 2022

Current levels:
pH: 8 (I just added acid in response - it was 7.8 2 days ago)
FC: 5.5
TA: 90
CH: 250
CYA: 80
Salt: 3700
Temp: 84

mknauss · May 21, 2022

I do not see any build up. The plates will get a bit of scale on them and will get sloughed off at polarity reversal. That scale will disperse and dissolve into the water.

The SWCG does not raise the overall pool water pH. If you used trichlor for chlorination before, it was acidic, so that is why you are now having to add acid. pH rise is primarily form aeration due to water features and wind, and the addition of fill water with TA in it due to evaporation.

Oly · May 21, 2022

What is your pool surface? Listing your pool system details in your signature helps the diagnosis.
Monitor your cells power output and salt ppm calculation for clues of plate fouling and scale.
Subtle changes in water chemistry can make a difference. Calculate your CSI on Pool Math and yes test your source water to anticipate the effects of summer top-offs.

joshf · May 21, 2022

Oly said:
What is your pool surface? Listing your pool system details in your signature helps the diagnosis.

Plaster. Not sure why my signature is T showing up.

Thanks for the tips. Sounds like that scaling isn’t a concern - it just looked different from when I installed.

Rancho Cost-a-Lotta · May 21, 2022

Your signature is there Josh. If you're on a smartphone, rotated 90 degrees to landscape view. Signatures don't appear in portrait mode.

Oly · May 21, 2022

With a plaster pool you will need to balance your water to keep your CSI between -.6 and .6 so keep an eye on your balance throughout the season and use your testing data in the calculation. Watch the performance of your new cell closely in the next several weeks and note any trends.