Cindy wrote:
My tapwater pH is 7.6.
The water that comes out of the RO filter is 6!
No wonder I can't keep my pH up. Do RO filters normally make the pH that
much lower?

Cindy
Yes they do Cindy. By removing most of the stuff from the water, they
remove the buffers from the water. But they do not remove the co2,
which decreases the PH.

But this will not effect the PH in your sal****er aquarium. The salt
mix has buffers in it.

If you have a low PH problem in a sal****er aquarium you need to find
out what the actual problem is, first you need to check your alkalinity.
If it is low, add some buffer, if it is not low, try to reduce the co2
levels by more surface agitation, protien skimmer, over flow etc. If
you have good o2 exchange, try to drop the co2 levels in the room with
the tank, crack a window etc.

For more info on this take a look at the Articles by Randy Homes-Farley
on advanced aquarist online magazine.
http://advancedaquarist.com/issues/may2002/chem.htm
http://advancedaquarist.com/issues/june2002/chem.htm
Kim Gross
www.jensalt.com