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Re: Hardness Test Kits

I am nervous about stepping in where giants tread, but something posted
recently confused me a lot. And since Mr. Booth is off the list for awhile,
maybe someone could help clarify this for me. 

Mr. Booth posted:

>Well, it's not rocket science. First one must buy the LaMotte Hardness test
>kit model PHT-CM-DR. Using a simple titration technique, one first determines
>the "Total Hardness" (their term) which is Ca+Mg. This test has a resolution
>of 4 PPM.  Then, using different reagents in the same test kit, one
>Calcium hardness (same resolution). By subtracting calcium hardness from
>hardness, you have now determined magnesium hardness.

Mr. Pushack posted:

>Ah HA! so you admit then that the Dupla test kit is NOT in fact a GH
>test kit but actually a _Calcium_ test kit and a "total hardness" test
>kit in disguise (whatever the heck THAT is). Is that permanent total
>hardness or total temporary hardness? AND since its a Dupla test kit,
>then aren't the units therefore in German degrees? What is the
>conversion factor from German to American degrees? 9/5 + 32??  ?;->

From Mr. Booths web page, it seems clear that GH is Ca + Mg concentration, so
I don't quite see what the problem is - the LaMotte kit (a very nice one I
might add) measures Ca+Mg or just Ca allowing you to calculate Mg.  Mr.
Pushack seems to have become very confused with the different nomenclatures
for hardness. And what does a Dupla test kit have to do with anything at all?
And the 9/5+32 is a temperature conversion.  

It looks to me like I changed information sources just in the nick of time. 

>And now I suppose you are going to tell us that potassium has nothing to
>do with hardness and therefore we should not be concerned about
>measuring it? 

My impression was that potassium has nothing to do with GH or KH. Also, I
remember that it is difficult to measure and most people depend on a proper
trace element mix (Dupla or PMDD) to insure they have enough. 

>I guess since potassium and sodium do not affect our
>ability to generate a lather, then they don't figure into the equation?

OK, I'm confused by this statement. 

Forrest King
Checking  Mr. Booth's WebPage for things I missed the first time