CH Question

[mwalling]

Hello fellow TFPers!

My CH level has dropped over the last month from 260 where it held steady for many months to 210-230 the last couple of weeks.

Question: Do I need to raise it by adding chems and if so, should I shoot for 300 or something else.

Latest test results:

FC: 8
CC: 0
PH: 7.8
TA: 70
CH: 210
CYA: 60
Temp: 90

Thanks!!

 

[Richard320]

The first question is how did it go down. Lots and lots of backwashing? Torrential rains? Coming out of suspension to form scale?

Calcium usually increases through evaporation and refilling. So if it went down there has to be a reason.

If there's nothing nefarious going on.... I'd do nothing. CSI is .05. That's almost perfect.

 

[mwalling]

The first question is how did it go down. Lots and lots of backwashing? Torrential rains? Coming out of suspension to form scale?

Calcium usually increases through evaporation and refilling. So if it went down there has to be a reason.

If there's nothing nefarious going on.... I'd do nothing. CSI is .05. That's almost perfect.

Hello Richard!

Not sure that your definition and my definition of torrential rain would be the same

June was significantly wetter this year than normal. We got about 8.5 inches compared to around 3 inches which is normal. Lost and added about an inch by backwashing a few weeks back. No signs of scale forming. Am I understanding that the csi is the number to be focused on and as long as it is well balanced, the CH can be a little low?

Thanks for helping me understand...coming up on my one year anniversary of pool ownership and still have a long way t go!

 

[Richard320]

Torrential to me means pool overflowing if you don't pump it down.

Seeing as your average depth is probably something like 50", 8.5" of rain will be 17% reduction in CH and CYA. That inch from backwashing is another 2%. 81% of 260 is 210. Of course, your Nature2 is constantly feeding CYA back, which is why CYA hasn't dropped as much. Or has it?

 

[mwalling]

Thanks for doing the math for me...seriously. That accounts for the drop. So I should be alright just letting it ride back up?

I am a TFP liquid chlorine guy...not Pucks (unless I'm away) or Nature2 additives for me!

Thanks very much for the explanation!