Calcium levels head south

[Mad Reefer]

For some time I have never had a problem with keeping CA at 400 to 450. Use kalkwasser reactor and occasional addition of additives. Recently the growth rate in my 155 has taken off with a 20% increase in new corals. I believe that this has put an added burden on my calcium need. It has recently started to fall, 2 weeks ago it was down to 380 so I added some additives. A week ago it was down to 350 so I read a article I believe in Reefkeeping Mag about CA additives and the use of Ionic balanced ones. So I hit it hard with Kent CB-A and part B 3 days ago. Check the CA levels last night and it looks as though they are still falling.

Did not add anything did water change instead. Is there a chance that I’m over shooting the levels and causing it to bleed itself off instead of stabilizing?

[David Grigor]

When you were adding CA additives, probably the ALK was also continuing to fall. The lower the ALK gets the less CA it can hold. Adding more CA and ends up driving down the ALK even more......

I would do a pretty big water change to try and get the balance back then start the increasing both ALK and CA in correct portions.......

Here's a good easy to read article to get you back in the right direction ( http://www.advancedaquarist.com/issues/nov2002/chem.htm )

[Spanky]

Mad

It's probably just being consumed. You might need to get a bigger kalk reactor, start using Ca additives, look into a Ca reactor, something like that.

Try keeping your Alk steady in the 8-9 range, then tinker with your Ca slowly over a few days. It will involve a bit of testing, but after about a week you should have a good idea of how much Ca you need. From there you can decide what action to take. After that, you can start raising your levels too.

FWIW, we have a SPS dominated 450. I add about 8-12 tsp of CaCl a day. It fluctuates.

HTH
Jerel

[Rick O]

Jerel what's your routine for maintaining alk?

[Jimbo]

Hi I have had the same problem with kent two part. Could not get the Ca above 350. I was also dripping Kalk at the same time. On one of Kent's competitors website they say you should add the buffer one day and on alternate days add the Ca part. They go on to say that you can precipitate Ca out even if you don't see it happening.

I suspect this is what is happening. It can be maddening. Or is is possible that the salifert test's just isn't picking up the particular ion of Ca. If you look at the ingredients on the Kent two part it has all kinds of stuff in it. I've switched over to seachem reef advantage Ca, Mag, Strontium. Still have had to add magnesium though. But my Ca is at 430 now.