Bumping mag via water change?

[SamMule]

Rather than dosing mag, I occasionally dump a bunch of mag chloride into my mixing water before a water change. I measure tank mag, use brs calculator, and then add that much mag to my mix to bump it back up. I shoot for around 1320, but usually don't bump it until it's 1280 or so.
I have been doing this for quite some time now, with good results. Have yet to see anything that suggests this is any more stressful than a regular water change.
Seems so much easier than messing around with a dosing pump.
Anyone else doing it this way?
How about problems with this approach?

/discuss

 

[DanyL]

I personally raise it through several days with a doser when it goes below 1260ppm-ish to around 1350ppm.
But honestly, I wouldn't be worried too much about raising Mg too fast, especially in these amounts.

Another point is, well.. don't change what works out for you :)

 

[chipmunkofdoom2]

There's nothing wrong with this approach in general. You just have to consider salinity, especially with an element like magnesium. By increasing magnesium, you will raise salinity. If you add more freshwater to adjust your salinity down after adding the magnesium, you're essentially diluting every other major component except for magnesium.

To do this right, you'll want to mix up your new saltwater, get it to the salinity you want, then add the magnesium you want, and don't adjust salinity afterward.

 

[DanyL]

@chipmunkofdoom2 Good point, however it isn't any different than using the Baling method as is.

Ionic balance is kept either by using Tropic Marine's Sodium Chloride free salt, or by dosing a mix of Magnesium Chloride + Magnesium Sulfate as the 3d component together with trace elements while keeping salinity in check.

 

[Randy Holmes-Farley Verified Community Expert]

Rather than dosing mag, I occasionally dump a bunch of mag chloride into my mixing water before a water change. I measure tank mag, use brs calculator, and then add that much mag to my mix to bump it back up. I shoot for around 1320, but usually don't bump it until it's 1280 or so.
I have been doing this for quite some time now, with good results. Have yet to see anything that suggests this is any more stressful than a regular water change.
Seems so much easier than messing around with a dosing pump.
Anyone else doing it this way?
How about problems with this approach?

/discuss

That is a fine way to add it. Magnesium depletes quite slowly. I never added magnesium directly to my tank, I just always boosted the water change water by the same amount every time.