using citric acid to remove metal stains...

Interesting stuff, thank you!

Today I picked up the baking soda for raising TA, and will get the CYA and calcium tomorrow.

No, I wasn't too lazy to test other things last year. :p I just skipped the salt test. Last year I ran the Autopilot with it reading 2800-3000ppm (now it's 20% higher).

My CYA is about the same as it was last year. I added some this spring because the pool overflowed with a bit with the winter rains, diluting it. That's why I had to add quite a lot of salt too. In any case, I will bring it up to the recommended levels.

Be sure to only raise the TA by 10 ppm. You want to keep it at 70. (You could also just leave it at 60 ppm for now and if and when it drops below bring it back to 70 ppm and not higher! )
You have never said how big you pool is so I cannot help you with dosing info but for everh 1000 gallons a SCANT 1/4 cup of baking soda will be in the ballpark to raise the TA by 10 ppm.
I would put in 3/4 of the amount you need over a period of several days--a small amount each day (because you just did the stain removal and you don't want pH to jump quickly lest the stains return., wait 24 hours after the last addition, adjust pH to 7.6 if it is higher (use your acid demand test if you have one)--If it's lower don't worry too much about it, wait another day your TA.
If it it still too low start adding the remaining 1/4 of the baking soda left over a few days and repeat the pH adjustment and testing.

I would not do this until you have finished with all the stain removal and your chlorine is holding properly.

Pool size is in my signature - 27,000 gallons. :)

I only put in a one pound box of baking soda so far. (The pool calculator site says I'll need five.) I had to add water last night and didn't want to bring up the pH too quickly, just like you wrote. I will hold off until I can get in there with the Vitamin C tablets to finish off my stubborn stains. (And get the chlorine stable.)

I'll look for calcium hypochlorite at the pool store (my once-annual trip, I suppose) to try to hit two birds with one stone. I realize that more calcium will be needed than just what is in chlorine though.

One more thing on the salt readings from the Autopilot vs. using a test kit. I had to look it up to make sure I hadn't "mis-remembered" that the reading will be affected by water temperature:

http://en.wikipedia.org/wiki/Electri...ure_dependence

My water is about 78-80 degrees now. I don't know off-hand what temp the SWG would have been calibrated at. I'm not too concerned about that since I can test once each spring to make sure I'm in the proper range. I really like having a saltwater pool - the reduction in maintenance is wonderful.

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Originally Posted by river-wear

One more thing on the salt readings from the Autopilot vs. using a test kit. I had to look it up to make sure I hadn't "mis-remembered" that the reading will be affected by water temperature:

http://en.wikipedia.org/wiki/Electri...ure_dependence

My water is about 78-80 degrees now. I don't know off-hand what temp the SWG would have been calibrated at. I'm not too concerned about that since I can test once each spring to make sure I'm in the proper range. I really like having a saltwater pool - the reduction in maintenance is wonderful.

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The AutoPilot IS temperature corrected (this is why the output fluctuates in the readout with temperature, it's the temperature correction at work.)
The chromate/silver nitrate test for chloride ions is not without it's own set of problems so it is not the final word either. My rule of thumb, if the two readings are within abut 800 ppm you are certainly in the ballpark. I really don't expect more precision than that nor is it really needed.