Mg numbers strange

[joekool]

I realized that my Salifert test was out of date by 2 years so I bought a new one that expires in 2021.

Test with old is 960 and new is 1590. All the water in the system is fritz RPM and it’s Mg is listed as a max of 1400 at 35ppt. I have not added any Mg to the water.

I didn’t want to start dosing anything until I figured out the Mg.

Not sure why it’s so high.

 

[EmdeReef]

My guesses would be:

- test kit off
- bad batch of salt or salt settling during shipping
- dosing? If you dosed any mg before

Have you tried testing freshly mixed salt?

 

[WWIII]

Whenever I was using Fritz (for almost 2 years). My magnesium would always test at 1500 or slightly higher on fresh mixed salt and in my tank. The tank never seemed to mind, but I do wish it was slightly lower.

 

[jtl]

Imo Fritz salt runs very high on Mg. I stopped using it.

 

[EmdeReef]

FWIW 1600 is fine, shouldn’t cause any issues.

 

[joekool]

I seem to remember that when I used to use the red sea coral pro mix the read label as it had higher amounts in it.

I'm going to assume that it's the old test kit that's off and not the new one. I've never had a bad salifert in all the years I've been using them.

Wish I hadn't bought all that Mg mix when I ordered the new test kit. Guess I'll have plenty.

I'm not new to dosing but I am just starting it on my new system. Wanted to make sure Mg was correct before dosing Ca or Alk for stability.