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Re: Hardness in ppm

>From: Paul Sears <psears at nrn1_NRCan.gc.ca>

>	The point is that _both_ are derived from _molar_ concentrations,
>which _are_ the easiest to use.

Sure.... but only if you know how to calculate molar concentrations! <g>

Let us practice:
 "atomic weight in g per Liter = 1 mole" (in mg/L = 1 millimole). 

 For example, 100 mg/L CaCO3 = 1 millimole CaCO3.

If I got this right I will say it 10 times. <g>

>> I decided to change my opinion about units: ppm
>> is really the preferred way to present hardness. 
>	ppm of _what_?  The usual problem is that people don't say, and one
>is left wondering.  

Paul, you got me that time! <g> On previous APD posts, I had been saying
the same thing!!! i.e. "ppm of _what_?"

GH and KH are odd units to use in lots of ways, but at
>least one is in no doubt what they are.

I think this conversation has gone full circle... or maybe has been around
the block a few extra times <g>. Several people have already said that
degrees hardness have had many definitions in the aquarium literature and
unless it is footnoted each time used, they may (or may not) mean the same

Regarding this thread, "enough is too much"