Alk Issues

FSOL

New member
Hey guys,

So here's the slight problem I'm having. I get my Ca and Alk at nice levels (Ca around 460, Alk around 9-10dkh). Then I start my kalk drip. For the kalk mix I use 2 teaspoons/gallon of water, so it's very saturated. And I start the drip of about 2 drops per second.
The problem is that my Ca level stays more or less stable around 460, but my alk starts coming down to 7dkh.

I always thought that once your Ca and Alk levels are balanced, the kalk drip is supposed to keep both of them synchronized and stable. Why's my alk dropping? I have to keep adding alk additive every week to get it back up.

By the way the Mag level is 1380ppm avg.
 
First, there is no season to have the Ca++ and Mg++ that high. Second as you raise the Ca++ and Mg++ the Alk demand becomes higher. Third, Alk is not used just for a Ca++ to attach itself to a carbonate ion, such as coral building. There are many reactions in the tank that use Alk, so often the Alk demand is higher than the Ca++ demand.

When Do Calcium and Alkalinity Demand Not Exactly Balance?
http://reefkeeping.com/issues/2004-12/rhf/index.htm
 
Thanks Boomer.

I always thought Ca of 460 and alk of around 9 is pretty much the standard and what people usually aim for, so why is it high? I've noticed that if I don't interfere and add Ca and alk separately, and just let the kalk drip do its thing, the Ca stables out around 420 and alk around 7dkh.
 
He's just saying it is not necessary. Natural seawater is 420 calcium and Mag is 1280. A lot of folks target 9 dkh for alk because it is right in the middle of the recommended range and allows for a little test kit noise. Most target 1290-1350 for mag.
 
FSOL

I've noticed that if I don't interfere and add Ca and alk separately, and just let the kalk drip do its thing, the Ca stables out around 420 and alk around 7dkh.

And if you can do that, as you say, there is no reason to raise them higher, as it is not needed and is just more work/cost for you to be adding other sup's separately :D

What you have FSOl is ideal and is what all would wish for:) To drip kalk only, with kalk being a 100% balanced buffer and to have the Alk, Ca++ and pH at NSW. Kalk adds no unwanted ions to the tank water. When you add these other sups' you are adding unwanted ions, such as Cl- and Na+.
 
I always thought that once your Ca and Alk levels are balanced, the kalk drip is supposed to keep both of them synchronized and stable. Why's my alk dropping? I have to keep adding alk additive every week to get it back up.

Dropping alkalinity is a sign that you are not adding enough to meet the demand. The calcium drop that accompanies a 2 dKH alkalinity drop is only 13-14 ppm, so you'd hardly notice it. But you need to dose more of both. :)

I show that in this article:

When Do Calcium and Alkalinity Demand Not Exactly Balance?
http://reefkeeping.com/issues/2004-12/rhf/index.htm

ahemmm

FWIW, I and others in this forum often answer questions from the bottom (oldest) up, so bumping them moves you out of the queue. :D
 
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Thanks for the help guys. I guess I'll be satisfied w/ the parameters I got and not target those higher values.
 
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