I thought I understood water hardness...

[Paul Evans <pm_evans@yahoo.com>]

I have a Tetra water hardness test kit.
According to it, my tap water is

KH = 10 degrees
GH = 15 degrees.

>From another kit the pH is 8.2 but that is 
not part of my confusion.

As I understand it, KH is the carbonate 
hardness i.e. the mangnessium and calcium
ions.  GH the non-carbonate hardnes i.e.
the positive metal ions other than 
calcium and mangnessium.

My confussion started last night.  I got a 
ion exchange water softener for my house.
Not for the fish tanks.  On a whim I decided
to measure the hardness of the softened water.
This is what I got.

KH = 9 degrees
GH = 1-2 degrees.

I thought the ion exchanger was supposed to
exchange sodium or potassium (potassium in 
my case) for magnessium and calcium thus 
reducing the carbonate hardness (KH) and
generally leave the non-carbonate hardness (GH)
alone.  Where have I gone wrong?  Is it possible 
the Tetra (KH) test solution actually reacts with
the carbonate ions which would not be affected
by the ion exchanger?

Paul Evans



_________________________________________________________
DO YOU YAHOO!?
Get your free @yahoo.com address at http://mail.yahoo.com



-------------------------------------------------------------------------
This is the apistogramma mailing list, apisto@majordomo.pobox.com.
For instructions on how to subscribe or unsubscribe or get help,
email apisto-request@majordomo.pobox.com.
Search http://altavista.digital.com for "Apistogramma Mailing List Archives"!