Stable: CA yet declining KH

[JD'sReef]

On today's test, my CA levels were 435ppm (consistent with past months), yet with this my KH level has dropped from 10.6dkh (test taken 3/07/10) to 8.4dkh. I do not understand how this is really possible unless it could have something to do with the algae destroyer (not working by the way) I dosed the tank with back on the 13th of this month.
Currently I am adding 3tsp of kalk to my top off water; would adding another 1/4 tsp on top of the 3 (totaling 3 & 1/4 tsp), help this situation? I feel that this would also increase my ca levels, rather the just stabilizing the KH.
Please advise!
Thanks,
J.

 

[JohnK]

Have you repeated the tests? It could be as simple as test error. (don't forget, hobby grade test kits always super precise )

 

[JD'sReef]

Jim,
I did a second test directly after that (at a much slower rate) with "around the same results".
Just back me up on the fact that adding more kalk powder to my mix will also raise the CA level in conjunction to my KH level. I think I will just do another Alk test tonight so see if it may have just been user error last night, since I do not see how this is possible.
Thanks,
J.

 

[DoctaQ]

an alk drop of about two like you mentioned here corresponds with only 10ish ppm of calcium use, its perfectly normal.

 

[stingythingy45]

There's nothing wrong with 8.4 dkh,I'd leave it alone.And no,adding more kalk to top off water wont raise anything,but will maintain both a little better.Only so much kalk can be added to ro water,like 2 tbs.
Most folks use 2 part for minor adjustments,me included.

 

[KSC]

You can only add 2 teaspoons per gallon of kalk powder to 1 gallon of fresh water. Any more isn't harmful, it will just fall to the bottom because the water will become saturated.

 

[wrassefan]

baked baking soda

 

[JD'sReef]

Doctaq: I am a bit unsure of what you are informing me of here. Are you telling me that my CA=435ppm and KH=8.4dkh are in perfect unity?
Stingything49: I was thinking the same thing today after my Re-Test (which came out to about the same dkh reading), I was just trying to stop a major crash from happening in the weeks ahead.
Wrassfan: I appreciate it, but there is to much at steak with making my own KALK powder.
Thanks everyone.
J.

 

[JohnK]

Ca and alk are used up in a specific ratio, that's what Doctaq is referring to.

It sounds like your levels may have both dropped a bit, but the ca appears the same (test error range) even though it likely dropped 10 or 20 ppm. 435 is pretty specific, given the limitations of our test kits, id consider it to be "around 400-450" if your test says 435.

 

[JD'sReef]

Thanks,
I realize that CA and KH are used in a equal ratio, but is there a chart that shows a direct relation between these two levels? I have seen one in the past and wold love to find that web page again.
Also, is there a test kit with more accuracy then others? Currently I am using salfert kits, but is there and easier one to purchase with less margin of error.
Thanks,
J.

 

[DoctaQ]

the margin of error is not that important, because as long as its pretty consistent it doesnt matter what it is exactly, precision is more important than accuracy here.
i think one meq/l which is equivilant to 17 or so calcium carbonate equivilant, i think 40% of which is calcium, when you break it down, you only have a tiny amount of carbonates in water and a huge amount of calcium naturally, ca will almost never seem to go down.

totally throwing out numbers here but
75ppm carbonates
400+ppm calcium.

by the time the KH drops below 6 or so, coral will stop growing so it wont drop any more, also meaning that the 20 or 30 ppm of calcium you used might or might not even show up on your test.