 Re: DKH
Was wondering if anyone knew what we have so many different Harness measurements but use the German degrees Carbonate Hardness (DKH)?
We see German as they have had the most input to this hobby, i.e, Tunze, Dupla,etc.. for both the Planted Aquaria and Reef Tank.They and the Dutch where at it way before we are.
We should be using a unit that as real chemical meaning , such as meq/l which is what about half of the people in this hobby use.
George, who wrote this, is a little confused on terms
To summarize:
Carbonate hardness (KH) is NOT the same as alkalinity. It can have the
same value as "total hardness", but cannot be larger than TH, even if
the measurement says so!
Alkalinity, in the strict sense, is independent of carbonate hardness,
but often parallels it. It is a measure of buffering capacity.
Carbonate hardness is not the same as alkalinity, it is part of Alk but what he doesn't know is the test kits we use are NOT measuring carbonate hardness but Alkalinity. Even though the kit says carbonate hardness it is alkalinity that it is measuring, not carbonate hardness
Alkalinity is NOT the same thing as Buffer Capacity, this is a misnomer. Alk is the ability to withstand downward trends in pH , whereas Bc is the ability to withstand both downward and upward trends in pH. Bc also takes into account ions, to a small degree, such as Ca,Mg, etc. and Ion pairing. As far as Bc goes NSW has almost nil Bc, as Bc takes place when half of the principal buffer is an acid and the other half is a base. For NSW this at a pH of 9 or 6. At either of these pH's it is difficult to change the pH by normal means.The Bc and Alk equations are not the same but very closely related, as is actual carbonate hardness is to Alk.
Yes, there are other units.....many
Just a couple;
French = .56 dH
English= .8 dH
American= .056 dH
International =dH / 2.8 =meq/ l
Furthermore, there are different types of each, i.e. German dH as, Ca0, Ca, Ca(HOC3)
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