bad test kit?

mfinn · Jan 5, 2014

Anyone buy a new test kit and get odd numbers?
I bought a new Salifert Mg test kit a few weeks ago and the first 2 weekly test showed my mg level in my 50 was at 1600ppm.

About a month ago using my older test kit ( exp. 3/12) my mg was at around 1100. So I added some Tech M that I had.
Didn't test after that for 2 weeks.
The first test with the new test kit last week ( Exp. 7/16) showed the level at 1600.
I was a little shocked, ( thinking that the old test kit was bad and I over dosed ) but had 20 gallons of fresh saltwater mixed, so I figured that would drop the mag down some.
This morning I have another 20 gallons ready, so I did my tests and the mag is at 1600 again.

So I tested my new water ( Reef Crystals) with the new test kit and it says that water is at 1600ppm.
This just can't be right.
All water for this tank is ro/di and it tests at 0 tds.

So I tested my tank water with the old kit and it reads 1170ppm.

Last week test results

CA. 440
Alk 7.4
PH 7.9
MG 1600

This weeks test results
CA. 430
ALK 7.4
PH 8.0
MG 1600

duke4130 · Jan 5, 2014

I have had this issue one with a Salifert magnesium test kit.... It kept reading 1400ppm for 2-3weeks till I realized that something was wrong. I normally need to dose 30ppm-40ppm in mag once a week... I went out and purchased a new Salifert test kit and sure enough it was down to 1250ppm

mfinn · Jan 5, 2014

duke4130 said:
I have had this issue one with a Salifert magnesium test kit.... It kept reading 1400ppm for 2-3weeks till I realized that something was wrong. I normally need to dose 30ppm-40ppm in mag once a week... I went out and purchased a new Salifert test kit and sure enough it was down to 1250ppm

What was the expiration date on the bad test kit?