Haven't received any pictures at poolforum@gmail.com . . .

While your calcium is a little low, I'd hold off on adding any now. You're thinking about removing FAR more calcium with an acid wash, then you would with a year of slightly low calcium pool water.

But, get your pH up to at least 7.0. Then I'd recommend 3 things:

1. Try ascorbic acid in a sock on a badly stained area.
2. Also try "Iron Out" in a sock on a similar area.
3. And finally, tell me what Jack's chemical they are recommending: you may be able to get some THAT chemical in a bagged version somewhere, and try that before you get a bunch.

Good luck!