azatoth: Thanks for your help. I was hoping for a simple answer to a
complex question, which I couldn't state precisely. (By the way, I am
a chemist) My problem is: I have an outdoor pond of 1500 gallons at a
pH of 8 to 8.5. It is highly buffered, and I cannot precisely give the
degree of buffering. I would like to achieve neutrality by addition of
HCl and was hoping to get a ballpark figure from my question. I know
the titration curve is steep near neutrality.
 I will have to bite the bullet and have my pond water titrated. I am
retired and can't do it on the job. Thanks for your research.
knowitall22