Alk and calcium

[chrali]

My tank has been running on auto pilot for quite a while now. I just tested my alk and calcium and noticed the alk was around 7.5 and calcium was over 500. Both tests were year old Salifert. Does this make sense? All I have been doing is top off and Kent calcium lately.

 

[Percula9]

I would get new test kits to verify those readings. Try API kits.

 

[Insainoreefer]

Are you running a calcium reactor?

 

[Duane867]

Or dosing anything ?

 

[rbursek]

Ca could be that high if you have been doseing and not testing to see what the levels were.

 

[chrali]

I have been dosing with the Kent calcium about a capful a day. I really don't have much coral in there. I lost most of it about a year ago durring a move. Pretty depressing. That's why I haven't been doing to much with it. I'm looking to get everything up and running properly again. I haven't seen any coraline grow so I though my calcium was probably too low (maybe it's my lights). I should have been testing all along. I guess my main question would be how the calcium relates to the alkalinity?

 

[buckeyegirl]

I believe low alk allows the water to hold more calcium without precipitating out. Someone please correct me if this is wrong cause I'm still a newbie but this is what I have read.

 

[David Grigor]

<a href=showthread.php?s=&postid=12378057#post12378057 target=_blank>Originally posted</a> by chrali
I guess my main question would be how the calcium relates to the alkalinity?

When calcification occurs the rate of usage is approx. for every 2.8dkh of Alkalinity, 20ppm of CA.

So if you have ony been using a Calcium additive it would stand to reason your CA is much higher than your Alkalinity.

You should be adding supplments for both Alkalinity and Caclium in the proper ratio if your wanting to maintain your levels.

 

[bertoni]

I agree that supplementing both calcium and alkalinity is needed to support stony coral or coralline algae growth. This system probably doesn't have much of either, so you could likely stop dosing the calcium.