BRS Magnesium mix question

[johnike]

I just finished dosing my first gallons of soda ash and calcium chloride.
I have a pouch (000315) of BRS Magnesium mix that according to instructions is to be added after exhausting said first gallons.
My question is, do I still add it even though my Magnesium is steady at 1395 now?
Thanks, John.

 

[homer1475]

I wouldn't add anything until your tests call for it.

I use the BRS Calcium and Magnesium mix with baking soda as my alk. I only add mag when my tests call for it. In my case I use about 20fl OZ of mag to about 2 gallons of alk and cal.

 

[Martin Kuhn]

I just finished dosing my first gallons of soda ash and calcium chloride.
I have a pouch (000315) of BRS Magnesium mix that according to instructions is to be added after exhausting said first gallons.
My question is, do I still add it even though my Magnesium is steady at 1395 now?
Thanks, John.

+1
You shouldn't dose Mg if the levels are already in a (too) high range

M

 

[bdare]

Knowledge is power. If you understand how Ca, alk and Mg work together you will be at a great advantage and not have to worry about those types of instructions.

http://www.advancedaquarist.com/2003/10/chemistry

Magnesium keeps help saturated levels of Alk and Ca in solution. I always dose Mg before Alk and Ca to help prevent precipitation.

 

[johnike]

The only reason I ask, is BRS says in their instructions to use the Mag mix after depleting the first gallons of Alk and Ca.
I understand the relationship between Mag, Ca and Alk.

 

[DivingTheWorld]

IME Mag depletes VERY slowly and you're already at a good level. I don't dose Mag at all in my tank. I just do water changes with Mag at around 1500-1600 and it maintains it in my tank above 1400.

Dosing mag now will just increase your Mag, which generally isn't dangerous under 1900 or so, but is totally unnecessary.

 

[Scorpius]

I wish BRS wouldn't say to add the magnesium mix after using a the Alk/Ca. Its foolish to just add something because. I test then add as needed.

 

[johnike]

I wish BRS wouldn't say to add the magnesium mix after using a the Alk/Ca. Its foolish to just add something because. I test then add as needed.

Thank you.
And everyone that replied, much appreciated.

 

[bertoni]

I agree that you should let the testing be your guide to dosing. The BRS formula is a compromise to control cost, so it does tend to shift the ionic balance some, but water changes should handle that. Dosing the magnesium part is more likely to be useful for systems that don't get water changes.