How much to start dosing?

blkhawk10 · Feb 6, 2016

So...I'm a little confused as to how much alk and calc I should start dosing to my tank if my levels are stable now and I want to keep them there. I'm seeing a reef calculator as a means to figure out how much of each to add if you levels are low, but I can't get any info as to how much to dose if the levels are stable. Any help would be appreciated.

ReefQueen · Feb 6, 2016

I just went through the same thing. I was also under the impression that you have to dose in the beginning to maintain. But I was told you do not start to dose until your levels start to drop. I am sure some of the experienced doses will chime in shortly

Randy Holmes-Farley · Feb 6, 2016

If alkalinity is stable, then you do not have ongoing demand for calcium and alkalinity that would require supplementation.

What is the alkalinity now?

JimWelsh · Feb 6, 2016

Step 1: Test alkalinity note the time of day. Call this Alk#1
Step 2: Wait N days without any dosing.
Step 3: Test alkalinity again at the same time of day. Call this Alk#2
Step 4: Calculate the average alkalinity drop per day: (Alk#1-Alk#2)/N.
Step 5: Base dosing on average alkalinity drop per day.

Clearly, the larger you can make "N" (without stressing your corals), the more accurate your calculated dose will be.

blkhawk10 · Feb 6, 2016

my alkalinity is 9 dkh...I had to raise my calc up the other day cause it was too low so I was under the impression its time for me to start dosing.

Randy Holmes-Farley · Feb 6, 2016

blkhawk10 said:
my alkalinity is 9 dkh...I had to raise my calc up the other day cause it was too low so I was under the impression its time for me to start dosing.

If the alkalinity has not depleted much relative tot eh salt mix, then the calcium hasn't either, since they have to be used together in a certain ratio, but calcium might be low because the salt mix doesn't have as much calcium as you want at the salinity you used.

I'd just keep monitoring the alk, as Jim suggests, and when it has dropped to below about 8 dKH, I'd look to begin dosing both calcium and alkalinity.