2 part mag dosing

[btb72]

I'm setting up a new tank and am trying to figure out the best way to go about setting up the 2 part. Do most people use a 3rd doser for the mag

 

[shih87]

I'm setting up a new tank and am trying to figure out the best way to go about setting up the 2 part. Do most people use a 3rd doser for the mag

Not sure others, but even I did not use 2 part for KH and Ca, but similar idea of solution and do use up to four dosers for KH, Ca, Mg, and K+ separately

 

[Reef Frog]

My consumption is low enough that infrequent dosing by hand is all I need in my 65g mixed SPS/LPS with steady growth. Alk & calcium are dosed automatically.

Personally I'd wait until setting up a dosed for magnesium as you may get what you need from water changes. I'd still test regularly as everything can change over time.