Corraline eating up my Ca and Mg?

[Llarian]

I've been trying to get the Ca values on my 20G nano a bit higher than they like to hang out at, but I really don't seem to have much success for any period. I'm dosing kalk as 100% of my topoff (more or less saturated, although its not through a reactor at this point. It seems like the values are going down over time however. (Even with regular water changes with IO)

Values a few months ago:

kH: 3.31 meq/l
Ca: 370 ppm
Mg: Not tested

Values today:

kH: 2.70 meg/l
Ca: 350 ppm
Mg: 1125 ppm

The Ca and Mg are inline with each other, although the kH seems out of balance. The only thing that's changed is that I have significantly more corraline than I used to, since I only clean the front glass and let it run wild on the sides and rear. (And boy has it!) The only stony corals I have are a small candy cane and small favia, neither of which is growing particularly fast, although they seem happy.

What's leeching all my Ca? I think a Ca reactor is overkill on this small tank, but it'd be nice to be able to find a semi-automated way to keep those levels a little higher.

Suggestions?

-Dylan

 

[wrightme43]

Well Kalk, and bionic or some other two part additive may work for you.

 

[Llarian]

Dosing as much kalk as I reasonably can at this point. Bionic would probably do it, but I was hoping for a more automated way like I can do with kalk. =)

I'm lazy and like to watch the reef, not mess with it. hehe

-Dylan

 

[steve-s]

It's actually not uncommon to need to suppliment kalk dosing if you have a heavy stony demand. If you have a rather large wallet, you can look into a litre meter for the two part liq.

Have you tried a few teaspoons of vinegar in the kalk to eek out a bit more punch?

Cheers
Steve

 

[Llarian]

Intreresting. No, I have not. How much is reasonable to add? I recall reading an article about that last year sometime, but there were cons associated with that method.

-Dylan

 

[steve-s]

The only "con" would be the small possibility of the carbon source (vinegar) causing increases in bacterial levels. If not maintained, the bacteria die back which may result in an algae bloom. Otherwise, there really is no issue and will usually curtail algae growth. Since it is being dosed along with the kalk, pH will not be a concern since vinegar alone will create CO2 as it breaks down. The hogh pKa of the kalk will counteract those effects.

I would start off slowly at about 1 tspn/gal of RO, see how that helps and increase as needed to at most 3 tspn/gal.

Expanding the Limits of Limewater: Adding Organic Carbon Sources

Cheers
Steve