Mojo (and more troubling, CA) rising... is this possible?

Jesse Sunday · Sep 20, 2024

So a week ago, I added a 20ml scoop of Red Sea "Skeletal Elements Foundation ABC+" to my 150g tank... as you can see,the ALK and CA rose... well, the CA continues to rise...

Is this possible, or is something else askew? (Trident needing calibration?)

If I dose Alk, will that bring the CA back down?

Randy Holmes-Farley · Sep 20, 2024

There’s no scale on your graph to see how much it is changing, but at 468 ppm, you have plenty of headroom in case it is actually rising and isn’t just testing or salinity effects.

Jesse Sunday · Sep 20, 2024

Randy Holmes-Farley said:
There’s no scale on your graph to see how much it is changing, but at 468 ppm, you have plenty of headroom in case it is actually rising and isn’t just testing or salinity effects.

Thank you for your time and thoughts!

When you say "headroom," do you mean CA at 460-ish isn't a problem? (what would it have to rise to for you to be concerned?)

If it is, in fact, rising, what could be the cause?

Thanks again for sharing your knowledge!

Jesse

Randy Holmes-Farley · Sep 20, 2024

Jesse Sunday said:
Thank you for your time and thoughts!

When you say "headroom," do you mean CA at 460-ish isn't a problem? (what would it have to rise to for you to be concerned?)

If it is, in fact, rising, what could be the cause?

Thanks again for sharing your knowledge!

Jesse

Right, not a problem. I recommend 400-550 ppm calcium.

Calcium can only rise by addition, a salinity increase where everything rises, or by dissolution of calcium carbonate where alk will rise by 2.8 dKH for each 20 ppm rise in calcium. The last one is never a problem for calcium because alk becomes a problem much faster.

Jesse Sunday · Sep 20, 2024

Randy Holmes-Farley said:
Right, not a problem. I recommend 400-550 ppm calcium.

Calcium can only rise by addition, a salinity increase where everything rises, or by dissolution of calcium carbonate where alk will rise by 2.8 dKH for each 20 ppm rise in calcium. The last one is never a problem for calcium because alk becomes a problem much faster.

I am ALWAYS amazed at your depth of knowledge! Thank you so much! Have a wonderful weekend!