Please explain 2 part dosing

[Idech]

I have only used All for Reef in my tanks (3 years) and now I stopped using it. I have calculated how much cal, mag and alk are being consumed in a week (5 ppm cal, 7 ppm mag and 0,2 dkh alk per day) but I don’t understand why you only dose calcium and alkalinity. What happens to magnesium ?

I was thinking of using ESV Ionic 2 part (calcium and alkalinity) but should I buy ESV magnesium as well ? Are there any cheaper ways ? Please note that I don’t have any dosing pumps and would rather not get any. I prefer dosing manually.

Current or desired parameters :

Cal : 440 ppm
Mag : 1360 ppm
Alk : 8,5 dkh

Thanks for your help

 

[Randy Holmes-Farley Verified Community Expert]

There are many different types of two parts. ESV is a fine choice, but so are others.

I describe how they work here:

https://www.reef2reef.com/ams/how-a...-calcium-system-works-and-why-it-matters.958/