Calcium-magnesium

AgMa

Junior Poster
May 30, 2016
48
5
8
Hi,


I do 50% water change every Sunday from 100% R/O water. I replenish the water with calcium (15ppm), magnesium (5ppm) and bicarbonate soda. My question is:


Do I have to add only the quantity just for the water I change or for the whole tank?


The clean water, must have also 15ppm ca and 5ppm mg or the half?
 

Christophe

Subscriber
Lifetime Member
Oct 3, 2013
395
269
63
Albuquerque, NM, USA
For water hardness elements, add only for the new replacement water. Generally very little of these elements are depleted. The leftover water in the tank will still have plenty.
 

AgMa

Junior Poster
May 30, 2016
48
5
8
Another question. Why I have the same gh (6) then like first day?


I thought that gh would be high because till now I was dosing ca-mg accordingly the whole tank, not just for the water change.
 

AgMa

Junior Poster
May 30, 2016
48
5
8
I mean that if I'm doing wrong with this dosage (from what you say, I have to replace ca-mg only for the new replacement water while I was replacing for the whole tank) then why gh is the same?


I think that it had to be increased. Am I wrong?