This thread brings up a couple of points. Test results shouldn't be in a sig because they are a snapshot in time. Sig stuff is more permanent.
Duraleigh,
The sig has a link to a spreadsheet that I update (mostly daily) that has my readings. I try to take a full set of readings once a week, and otherwise just post FC,CC,TC, and pH. No actual readings are in the sig itself, you simply click the link in there and it shows you a historical of all of my tests.
Either im wrong or you need to recheck your CSI in pool math, or your test results. Using the following numbers, Pool math says your CSI is +0.48
17.4K gallons water
FC 7.5
Ph 8.2
TA 80
CH 325
CYA 40
Salt level I did not find on your spread sheet - so I used 0
Borate I did not find on your spreadsheet - so I used 0
Temp - I guessed at 87.
Your spreadsheet is diffiucult for people trying to help you to use. You dont list ALL of the water parameters every day. I had to scroll up and down a few times to find the most recent values for TA and CH. If you will note the TA, CH, and Salt and Borates each day at what you consider them to be if didnt test them. That would be more user friendly to us.
So, I would suggest review the values you used in Pool Math to come up with a -.08 wiith those numbers
Divin Dave,
The point here wasn't to bring anyones attention to my actual readings...I wanted to talk about this based on the logic and theory of it. Either it works based on certain parameters, or it doesn't. My numbers (or missing ones in the past few days) only clouds the question I wanted an answer to, which was "Is it ok to have a pH over 8 if the CSI shows balanced. JamesW has more or less correctly inferred my numbers (I think I have 3300ppm salt, a negligible difference), but the point of my question wasn't to ask about my specific numbers, but to ask generally about the practice. If I were posting this in the getting started board with a "what should I do" at the end of it, my numbers are definitely a must...for this question, I was more looking for theory and the science for it/against it and my specific numbers while not irrelevant, shouldn't be required to discuss this piece of minutiae.
Duraleigh,
If the CSI isn't a good measure and some of us seem hung up on it (and lots of discussion revolves around it), why do we even use it? If the formula is supposed to yield whether water is balanced, and the formula shows balanced water, why is it to be ignored when it potentially is cross to the general TFP chemistry? If we are to keep a CSI in the -.3 to .3 range, using the numbers JamesW put out there, I've got 7.7-7.9 that I can ride on to be within CSI but also follow TFP guidelines, and based on TFP guidelines for SWG:
"Adjust your pH to 7.5-7.6 and not any lower. Monitor your pH and when it climbs to 7.8 add acid to lower it back to 7.5-7.6 (This is also IMPORTANT!)"
I would NEVER be targeting a balanced CSI. In addition, some forum members (JoyfulNoise is the one I notice the most, and backs up what is said with great info and data) cites a reasonable guidance to maintain a slightly positive if not completely balanced CSI on newer plaster pools...something's gotta give somewhere, and is that something the TFP pH guidance, or the CSI? I'm not saying I have it in my head of which one, I'm just trying to sort out which should give deference to the other.