High Magnesium Level?

capdippe · Aug 28, 2010

I changed about 35 gallons on my 100gal tank over this last week. I then tested the water a few days later and got:

Salinity 1.026
Cal 400ppm
Mag 1600ppm
Alk 8.5
Am 0
Nit 0
Pho 0
temp 76.5-77.9 W/chiller

I've been using Brightwells salt for the last 4 months, and haven't dosed magnesium for almost 2 weeks. Is 1600ppm of MG hight for a reef tank? Should I be changing 50% to get it down?

My regular water changes have been around 25 gallons per week (a little everyday).

Thanks Reef Frontiers, Matt!

iroll253 · Aug 28, 2010

Dont ad anymore 1600 is fine i believe. Mine is 1450

NC2WA · Aug 28, 2010

what is pH..if stable then I would not worry about it, otherwise, WC will bring down level as long as you don't add anymore.

capdippe · Aug 28, 2010

Oh yeah sorry, the PH is 8.3.

capdippe · Aug 28, 2010

What would be dangerous level of magnesium?

mfinn · Aug 28, 2010

capdippe said:
What would be dangerous level of magnesium?

not sure what a dangerous level would be, but many people including myself have raised the mag level with Tech M up to as high as 1700 to 1800 to fight bryopsis.

NC2WA · Aug 28, 2010

my level was 1700 and I maintained it one week, then it slowly fell over the course of several weeks...For my 375g tank, it took several large WC to get it back to normal level which for my tank was 1200-1300.