Kalkwasser with elevated calcium?

Falcar · Mar 17, 2021

Hey all
I’ve been wanting to start dosing kalk as a way to manage my alk and calcium. Right now my alk is being consumed (and I’ve slowly buffered it back up) but my calcium doesn’t seem to go down and is around 550.
Any idea how i should make the transition to kalk? Or wait for the calcium to come down?

DxMarinefish · Mar 17, 2021

From what I gather about your post, you are not currently dosing Kalk, but your Ca is 550.

Are you dosing a 2part currently? If so you can stop the Ca dosing until it comes down to 440.

Just remember that Kalk has a tendency to raise Ca over prolonged usage as well.

Randy Holmes-Farley · Mar 17, 2021

How much alkalinity is being consumed each day?

Falcar · Mar 17, 2021

I've only been dosing ALK (soda ash).

I'm losing only about .5 DkH a day. The tank only has a handful of LPS/SPS at this point.

Randy Holmes-Farley · Mar 17, 2021

Falcar said:
I've only been dosing ALK (soda ash).

I'm losing only about .3 DkH a day. The tank only has a handful of LPS/SPS at this point.

That is pretty low, and the expected drop in calcium is only 2 ppm a day. Thus, it would take a long time to reliably detect a calcium drop and water changes with a high calcium mix might keep it propped up.

What you are dosing is fine until calcium comes into the lower 400's (assuming it is accurately measured in the 550 ppm range now).

IF you want the pH boost of kalkwasser without the calcium, you can use sodium hydroxide.

When you start the kalkwasser eventually, you won't need all that much. A calculator can tell you how much.