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cwegescheide
04/26/2006, 05:16 PM
Hey Randy,

Glad your back from vacation!! Where did you go? Anyplace really interesting? I'm sure you've got a slew of posts to respond to.. :D

Well here's one more. Is my tank using calcium quicker than Alk? The reason I ask is that my Alk has a tendency to raise quicker than my Ca pretty consistantly. I tested my MG and it seems to be around 1300 if not higher (its been a few weeks since I've tested)

My Ca is 420 and my Alk is 4.1 meq/l using sailferts. Doesn't seem to be keeping at porportional levels.

Also another thing. Would you think its entirely plausible that corals don't use calcium and alk at a fairly consistant rate? For several weeks my alk was rock solid around 3.5 meq/l and Ca 420.
I do have about 40 different species of acro's in my tank and they are growing, some more than others. 2/3 are decent sized frags and others are small colonies.

I'm also thinking that my PH probe in my Ca reactor might need to be recalibrated possibly? Its only been a few months if that I've had it in there. I'm thinking that maybe the reading in my neptune might have drifted and is actually lower than what it actually reads dumping a stronger solution of alk and ca into the tank? I was hoping to get my tank as stable as I can but its not really working out like I thought it could. I'd just like to not have to fiddle with the thing every week when I get home. Alk just always seems to creep up from 3.2meq/l to closer to 3.8 (sometimes higher) in the course of a week. Should I be able to keep my alk more consistant? I'm just worried about RTN etc from Alk imbalance.

sorry for the long post. Thanks Randy!

Chris

Randy Holmes-Farley
04/26/2006, 06:11 PM
There is no way for a tank to "use" calcium faster than alkalinity. Water changes with a low calcium salt would be one way to cause the effect, along with an inaccurate test kit.

However, when you add any balanced additive, alkalinity appears to rise faster (1 meq/L =- 2.8 dKH) for each 20 ppm rise in calcium.

This article details that effect:

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

Demand for both in the tank will depend on pH and alkalinity, being higher at higher levels of those.


We went to our vacation home in upstate NY, on Lake Ontario. :)

cwegescheide
04/26/2006, 07:19 PM
Thank you Randy. Sorry to keep bugging you about this stuff. Come to think about it I did just treat my tank for red bugs and did about a 30% water change. I used Tropic Marine salt.

Before this episode I would occaisionally give a little bolus of Ca if I noticed my Alk creeping up a little bit. After reading your article maybe I should have tried to decrease the output of my reactor a little.

Sounds like you had a nice relaxing vacation.. :)

Appreciate you help,
Chris

Randy Holmes-Farley
04/27/2006, 04:57 AM
I did, thanks. :)

You're welcome and good luck!