Magnesium test trouble

[gfox2]

I am using the Salifert test kit for Magnesium and during the last step the color of the regent does not change.What could I be doing wrong?

 

[disc1]

If the magnesium level is higher than what the kit will read you may have to refill the syringe and keep going. It will require a little math to figure the value. It's not too hard, but if you need help come post back here and someone will surely assist you.

 

[gfox2]

Thanks for the reply,but I don't think the tank is higher then the 1500 the test kit reads for at the high end.When I put the 1ml syringe in the test tube the color does not change.I am wanting to raise my Mag up to around 1600 becauce I have byrosis.

 

[thegrun]

It's possible you have a bad test kit, but I would try to add more Mag-3 regent to be sure. Some of the salt mixes out there are very high in magnesium and if you don't have much demand the levels can run over 1500.

 

[gfox2]

I use Reef crystals right now.

 

[gfox2]

So I retested and on the second vial of the regent 3 it turn to blue with .7 left in the vial.so what does my Mag read at now ?

 

[bertoni]

It's 1500 + 0.3×1500 = 1950 ppm.

I don't know whether the kit is working, though. I'd measure some freshly-mixed saltwater and get a second opinion on the kit.

 

[gfox2]

Would reef crystals have the Mag higher then 1500?Have never tested Mag before now

 

[Randy Holmes-Farley]

Not likely, no, unless you mixed up just a small part of a salt container.

 

[gfox2]

When I dose Tech -M and bring the Mag up to somewhere between 1600 and 1800 will it stay there?

 

[Randy Holmes-Farley]

The decline in magnesium due to calcification is generally very slow (~0-0.5 ppm per day, typically, sometimes a bit more), but water changes will bring that high level back to normal.

 

[gfox2]

The decline in magnesium due to calcification is generally very slow (~0-0.5 ppm per day, typically, sometimes a bit more), but water changes will bring that high level back to normal.

Thanks for the info

 

[kevinl]

I have tested reef crystals several times, Ca-500, alk10 to 11, mag 1500 to 1760. This is the usual range, I try to test each new batch of box's I buy.

 

[Randy Holmes-Farley]

Perhaps it has changed, but I'd be surprised if they altered the commercial recipe that much. Maybe your kit reads high, or your salinity is actually higher than you think?