Help 2x SN failing purity test

[Shiva_Story]

I have SN from 2 different suppliers in the Phillipines but they fail the Aquarium test.
My procedure is the following
Measure 2.5g of SN and dissolve in 500ml distilled water
Take 1ml of it And put into another 500 ml water
test it
Am i doing something wrong?

 

[ForestGhost]

Hey, I'm really no expert at all at this stuff but just wanted to add that other people have reported the same issue with DMC's SN and there have been lots of successful CTBs with that. Have you tried seeing how it reacts to blood? If you get a good result there that might be enough of a litmus test.

 

[losi]

if you put slightly more sn, it will give 0. you should put exactly or little less.