pH problems

[Keith Cheng]

We are having some problems with alkalinity of our water for which I hope 
someone has an economical, practical solution.  Starting with 
deionized water is not very practical for us, so we need to try to use 
tap water, which we currently charcoal filter.  Over the past year, the 
pH of our medium hard water (about 9 degrees hardness) coming out of the 
tap has been about 7.5, which climbs after recirculation, UV filtration 
and aeration to about 8.0 (perhaps due to chasing off CO2?), despite 
10%/day water changes.  Suggestions entertained so far include bubbling 
CO2 gas and adding buffer (such as Seachem's "Neutralizing buffer").  Any 
other ideas out there?

Thanks.

Keith C. Cheng
Division of Experimental Pathology
Penn State College of Medicine
Hershey Medical Center
Hershey, PA 17033
717-531-5635
fax 717-531-5301
kcheng at cor-mail.biochem.hmc.psu.edu