using citric acid to remove metal stains...

[river-wear]

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.

[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.

[waterbear]

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.

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.