Calc and Alk

[jakem42]

Hey all!
I measured my calcium and alk levels today and my calcium is at 410ppm and alk is 10.2dkh. I’d like to raise the calcium a bit closer to 430 as I’ve read that’s a better range. But I don’t want to raise my alk even further as I think it’s already kind of high. Any suggestions? I have mostly LPS corals. Thanks!

 

[Randy Holmes-Farley Verified Community Expert]

I think there is zero evidence that the calcium value matters at all in the 400-550 ppm range, but adding some with a calcium supplement (calcium chloride) is a fine plan.

 

[Randy Holmes-Farley Verified Community Expert]

What is the salinity? Raising the salinity a bit will also boost calcium.

 

[jakem42]

What is the salinity? Raising the salinity a bit will also boost calcium.

Salinity is 1.025

 

[Randy Holmes-Farley Verified Community Expert]

Raising it to 35 ppt (worldwide ocean average, which has sg = 1.0264)will boost the calcium to 433 ppm.

 

[jakem42]

Raising it to 35 ppt (worldwide ocean average, which has sg = 1.0264)will boost the calcium to 433 ppm.

Would that not increase the alk?

 

[Randy Holmes-Farley Verified Community Expert]

Would that not increase the alk?

Not much, and it will drop again. 10.2 —> 10.8.

 

[jakem42]

Not much, and it will drop again. 10.2 —> 10.8.

Okay thanks!