Magnesium not rising

[Vgyoung]

My mg has been around 1200 I dose magnion 7 ml for my 29g biocube ( recommends 1 ml per 4 gallons). I checked before dosing and 5 hours later levels are still 1200. This has been a problem for about a month. The reason I'm also concerned is Bc the mg won't rise same goes for my calcium ( I'm doing B-ionic along with alk).
These have been my levels every time I check my water before and after dosing for the past month.
Before dose
Alk 9.0/9.2
Ca: 400
Mg: 1200
After dose
Alk 9.8
Ca: 400
Mg: 1200
-
Salinity always 1.025-1.026
Do I simply just slowly add more until I see a rise? Do I increase magnesium and calcium or only magnesium? I'm new to dosing so any tips would be much appreciated( or any information I left out).

 

[eutimio]

It will take a lot of magnesium to raise levels. It is no surprise the level does not rise with 7ml.
It is recommended you don’t raise levels by more than 100ppm a day.

For example, B-ionic Magnesium supplement states that 1ml of their product in 1 gallon of water will raise Mag by 10 ppm.
Quick math says it’ll take 10 ml to raise the same gallon to 100ppm.

In your 29 bio cube that is more like 20 after rock and sand is added , you will need 200ml to raise Magnesium from 1200 to 1300.
I would do a couple 150ml doses in 2 separate days for a total of 300ml to raise it back to 1350.
Hope that made sense.

Edit: I would test after the 2 doses see where you stand and adjust from there.

 

[bertoni]

I agree that 200 ml sounds like a more reasonable dose, although I'd have to go through the math to be sure. You could just double the dose until you see a detectable result, and work from there.

The recommended doses are there for people who don't test. You can ignore them. Do they give the concentration, or more detailed instructions?