DKH info

Ok guys I've read through a few threads that contained my search param. but nothing was helpful and thought it would be more efficient to add a new thread. Instead of reading and reading. I apologize to all the redundant thread police!

Ok so I'm trying to get clear on an Alkalinity test. I use instant ocean test kit. First off to recap and ensure my understanding is correct thus far. Alkalinity test is a carbonate hardness test i.e hard water. The opposite of pH. It can be measured in several units, however I believe I've found DkH to be the most widely used. German Degrees for Carbonate Hardness. To do this we first need to get the mEq/L and then multiply by 2.8 to arrive at the DkH.

For those that have the same test kit. I first dropped a few drops of solution to get initial blue color, I then continue adding drops until water changes to yellow/green I then add the total number of drops (this I'm double checking), the initial drops (3) to the second set that made that color change (6) = 9. Divide by 2 = 4.5 *2.8 = 12.6. I don't know a healthy range. Nor am I positive I divide the total number by 2 or just the second set of drops.... any additional insight would be greatly appreciated. Please specify what unit of measurement your suggested range is in please!
Many Thanks,
Nick

 

SaltyZoo's Alkalinity Reading Conversion (meq/l / dKH / ppm CaCO3) Utility

hey Nick
you just divide 9 by 2.8 and your Alk is 3.21

you dont need to divide by 2 and then x 2.8

Or you can use the handy calculator above and type in the number you have and get the number you want

DKH is fine - its easier to work for me

Reef tank ranges are between 7 - 11 - so 9 is a good number to have and maintain IMO

Steve

 

Thanks steve, so by simply taking the number of drops and dividing by 2.8 and going backwards is giving me the Alkalinity mEq/l as equivilent to DKH. I guess I get confused that there are different measurements one and then there are different corresponding mEq/l for each type of unit of measure... Also when you say reef tank ranges from 7-11 I assume you mean drops of solution.
Nick

 

Reef tanks range from 7 to 11 dKh. You can think of dKh and meq/l as just two different units of measure, like inches vs centimeters.

Alk isn't the opposite of pH. It's a factor in determining what your pH is. pH is parts hydrogen, while alk is a measure of the carbonate and bicarbonate in the water. You're right in saying it's how hard the water is.

 

Blackravens posts explained it

but in a nut shell - DKH parameters in a reef tank should be maintained between 7 - 11


Steve

 

So i have a dkh of 12.6 if I did the rest right! I'm still uncertain if we count total drops from beginning to end or just the number to change blue to yellow... My ph is 8.0....

 

Usually it's total drops, beginning to end.

With alk of 12.6, make sure your calcium doesn't plummet and your magnesium is high enough to maintain them both.

 

No = you have a DKH of 9

3 drops +6 drops = 9 - so you have 9DKH

or 3.21 Meq

Steve

 

You guys can see where I find confusion. Steve the test kit says take the number of drops, divide by two and find the multiplier for which ever unit of measurement you want. In this case of DKH its multipler of 2.8... so 9 drops, divided by two would give me a mEq/l of 4.5 and then multiply by 2.8 gives me a DKH of 12.6....at least that's how I think it is and have been doing it but again I'm not certain. I believe a mEqL of 2.5 to 4.5 is ok while a dkh of 7-12 is ok.

 

Also, I have never tested for calcium or mag. I simply add iodine every week. I'm beginning to give thought to adding the others but almost dont' want to screw up a good thing. My limited corals are growing fine and fish seem happy. So I'm hesitant to dose anything else. I do water changes everymonth sometimes twice a month. Only small ones however 15%... my ph is 8.0....