New Salt Cell Fouling Quickly

[Seadweller]

I just installed a new salt cell 30 days ago, and yesterday, my control unit was lit up like a Christmas tree. "sLO" on the LED, and the "Check Salt" and "Check Cell" lights were on. Cell was reading "0000" salt level. I pulled and inspected the cell, and it was pretty fouled with calcium deposits, so I cleaned the cell and reinstalled it. It seems to be working properly again, but I have to imagine a 30-day cleaning regimen is going to reduce its life significantly. The CSI in the pool is a -.25, so I'm baffled as to why it fouled so quickly.

Any ideas? Would a small, weekly dose of sequestrant help?

Thanks!

 

[mknauss]

Share your Poolmath logs if you will.

Do you have scale flakes exiting your returns?

 

[Oly]

Test your fill water for TA, CH and pH and post those numbers along with your recent pool water tests. How did you chlorinate your pool prior to the recent SWCG installation?

 

[Seadweller]

No noticeable flakes coming from the returns. I'll see about testing the fill water tonight.

Thanks!

 

[Seadweller]

I've had the salt system in place for 8-9 years now.

 

[JamesW]

Where are you getting your numbers?

TA 73

CH 243

CYA 76

 

[proavia]

Download and use the PoolMath app.
Be sure to set it up to share your PoolMath logs to the forum.

The results shown in the pic in post #4 look like pool store test results.
We don't want to see those.
Post a full set of current test results from your TF-100.
Do you have a Taylor K-1766 kit to accurately test the salt level?

 

[Seadweller]

Where are you getting your numbers?

TA 73

CH 243

CYA 76

Those came from the pool store that I went to. My test results the same morning using my Taylor test kit were TA 80, CH 240, and CYA 70, so somewhat close.

 

[Seadweller]

Do you have a Taylor K-1766 kit to accurately test the salt level?

I do not, I use the Aquachek strips. The results from the strips are very, very close to what the pool store results indicate.

 

[JamesW]

Possibly a different type of scale, like calcium phosphate.

Did acid dissolve the scale easily?

 

[Seadweller]

Morning...I went ahead and ran a fresh set of tests just now, and here are the results:

FC 4.5
CC 0 (although I'll get a small patch of green algae on a wall still)
CH 375
TA 90
CYA 70
PH 7.8

Regarding the cell, the acid bath did dissolve most of it, but there were still thick flakes in the "grill" of the cell, and some pretty hardened deposits that I carefully removed with a small metal blade. Interestingly, I took out my old cell to possibly use as a backup, and a load of white chips fell from it. When striking the cell in an upright position, more flakes were dislodged and fell from the cell.

Something to note is that I have used Cal-Hypo 73% to try and maintain the chlorine level, since the salt system doesn't seem to be generating the same amount of chlorine as my prior cell, even though it's from the same manufacturer. All operating parameters are within spec (voltage, current, etc.). I believe I'm running it at 100% for at least 16 hours/day.

I've read where a sequestrant might help with cell fouling, but I'll rely on the combined knowledge of the experts here to guide me!

 

[mknauss]

Something to note is that I have used Cal-Hypo 73% to try and maintain the chlorine level

That is your issue. Only use liquid chlorine if needed.
Your cell should make plenty of chlorine. Just need to run it long enough.

 

[Seadweller]

Well, not what I wanted to hear, given that I just spent $100 on a box of the Cal-Hypo! Is there a salt-system-friendly granular shock I could use that won't cause the issue?

 

[mknauss]

Granular 'shock' is either cal hypo or dichlor. Neither is recommended.
Use liquid chlorine.