Which Alk Hanna checker?
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twilliard
Tank pests..
The difference is how they display the value to you
One takes a multiplication of .056 and the other requires no calculator
I use the PPM and over time you don't even need to do the math.
For instance my tank sits right around 164
One takes a multiplication of .056 and the other requires no calculator
I use the PPM and over time you don't even need to do the math.
For instance my tank sits right around 164
twilliard
Tank pests..
The DKh
Eckolancer
LED GURU
Dkh I think is a new one. The ppm one just uses a conversion to tell you what dkh your result is at.
Randy Holmes-Farley
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IMO, neither ppm not dKH are good units for alk (meq/L is the standard for scientists), but reefer history has many folks stuck in a ppm or dKH world.
Randy Holmes-Farley
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It is the units I rail against, not the device.
As I mentioned, the preferred units for scientists are meq/l (milliequivalents per liter). Those have a perfectly understandable meaning to any scientist in the world.
OTOH, the actual meaning of dKH or ppm calcium carbonate equivalents is lost on 99.9% of reefers, and might have little meaning to many scientists (especially dKH).
As I mentioned, the preferred units for scientists are meq/l (milliequivalents per liter). Those have a perfectly understandable meaning to any scientist in the world.
OTOH, the actual meaning of dKH or ppm calcium carbonate equivalents is lost on 99.9% of reefers, and might have little meaning to many scientists (especially dKH).
twilliard
Tank pests..
But to the standard home aquarist dKH is a standard is it not?
Randy Holmes-Farley
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For reefing, yes, but only because most kit makers force it so. If they used other units, reefers would too.
fab
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What is the conversion for ppm to meq/L?
And for dKH to meq/L?
Randy Holmes-Farley
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The Units of Measure of Reefkeeping by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2005-08/rhf/index.php
from it:
Alkalinity is a measure of the amount of acid necessary to reduce water's pH to the point where all carbonate and bicarbonate have been converted into carbonic acid (about pH 4.2 in seawater). In seawater, bicarbonate and carbonate provide nearly all of the alkalinity. Consequently, reef aquarists can use it as a surrogate measure for bicarbonate and carbonate which are taken up by calcifying organisms (Figure 1). The units of alkalinity can be meq/L (milliequivalents per liter), dKH (degrees of carbonate hardness), or ppm (meaning ppm of calcium carbonate equivalents). One meq/L = 2.8 dKH = 50 ppm CaCO3 equivalents. Seawater has an alkalinity of about 2.5 meq/L = 7 dKH = 125 ppm CaCO3 equivalents.
Sharvey103
ReefAddicted
Randy is absolutely correct. As a degreed chemist meq/l is preferred.
RobBaglieri
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coming from a chemistry background dKH means nothing to me. meq/l makes more sense. Never really studie the term alkalinity in school. Im used to buffers, buffering capacity, pH, pKa... where did this dKH come from?
Randy Holmes-Farley
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Old German term for degrees of carbonate hardness, used by water people and aquarium people there in the past.
Keen4
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europe?
Randy Holmes-Farley
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see post before yours
Keen4
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Yes it’s German
