Ca, alk, kalk puzzle

salty joe · Dec 6, 2017

My Ca was 400 so I added enough kalk powder to bring it up to 420. The odd thing is, my alk didn't budge from 7.6. I'm using Salifert tests and the alk test gives a pretty definite change-I don't get why the alk didn't go up as well.

BTW, Mg is 1260.

Randy Holmes-Farley · Dec 6, 2017

If the calcium actually rose, then the alk did too. The calcium test may just have enough error in it that you didn't see the exact calcium effect.

How did you add the limewater?

salty joe · Dec 6, 2017

I made a slurry and poured it in. Three batches over two days.

salty joe · Dec 6, 2017

I made a slurry and poured it in. Three batches over two days.

So a screen popped up that I had to log in and didn't think I got to post. I was already logged in-sorry about double post.

Randy Holmes-Farley · Dec 6, 2017

Slurry in fresh water may not be a good way since it may not dissolve into the water before you precipitate calcium carbonate onto it or around it. Slurry in tank water is even worse since precipitation will start in that slurry.

Much better to dissolve fully in fresh water and then add very slowly, dripping somehow.

salty joe · Dec 6, 2017

I only used slurry because I wanted to raise Ca and alk quickly while taking advantage of the Ca/alk balance in kalk.

Could it be that the freshwater kalk slurry raised the Ca but not the alk?

Randy Holmes-Farley · Dec 6, 2017

salty joe said:
I only used slurry because I wanted to raise Ca and alk quickly while taking advantage of the Ca/alk balance in kalk.

Could it be that the freshwater kalk slurry raised the Ca but not the alk?

Nope. [emoji3]