Another Alk Question

[phishlipripper]

Randy,

I have been reading over some Alk questions to check if mine is redundant or not. I didn't find one that is to similiar so here goes..........

I am using a Ca reactor. I do bi-weekly water changes I Check my water parameters before I do a water change then the day after to supplement anything that is out of whack.

Here are my typical results before the water change

Ca 370 ppm
Alk 1.7 me/L

I then restest after with minimal change. I will then boost everything back up to the "accepted" range and when I recheck before my next water change it always seems that my Alk drops way down compared to by Ca.

From reading your previous posts you have stated that Ca and Alk are used in a balanced quantity and by reactor supplies them in a balanced quantity. So why do you think that my Alk level is dropping so much faster?

I use baking soda for the Alk boost and drip with Kalk in the evening. I am getting a larger reactor also since I am expanding my system. I am also heavy in SPS and have three maximas and one huge squamosa. I have a several fish:

Hippo Tang
2 True percs
Sargassum Trigger
Coral Beauty
6 Line Wrasse
2 Banghai Cardinals
Spotted Mandarin
Square Spot Anthias
Lyre Tail Anthias
Green Chromis that I can't catch

What do you think?

:confused: :confused: :confused: :confused:

[aquababy]

One thing you might consider - your magnesium level. Mg should be 1350 - 1500ppm and will stabilize CA and ALK. Check it out - it might be what is wrong or part of the problem anyway..

[phishlipripper]

Yeah, I was thinking about getting a Mg test. I just haven't ordered one yet. All the LFS by me don't carry them.

Do you know anyone putting Dolomite into their Ca reactor to supply Mg in a balanced amount. I think if you add 10% by weight of your total media it may do it. That way you don't have to add supplements.

What do you think?

phish

[Randy Holmes-Farley]

From reading your previous posts you have stated that Ca and Alk are used in a balanced quantity and by reactor supplies them in a balanced quantity. So why do you think that my Alk level is dropping so much faster?

When you are using a balanced additive, and are not adding enough, alkalinity always seems to drop faster simply because there is a big reservoir of Ca++ in seawater, and hardly any alkalinity. So when corals take out some CaCO3 in a balanced fasion, alk seems to drop a lot (1 meq/L or 2.8 dKH) for a seemingly small change in calcium (20 ppm).

So I expect that you are simply not getting enough boost from the reactor.

I'd follow the guidelines in this article to tune the reactor:

Simon Huntington's CaCO3/CO2 reactor article
http://reefkeeping.com/issues/2002-05/sh/feature/index.htm