Help What is the best way to test SN

[qwe78978213]

There's a comment on the forum saying that the swimming pool test kit is not accurate,
and it says I have to use reagents.

My test results also had many errors with the reagent.

What is the best way to test if the SN I have is of high purity and really usable?"

 

[uzuf86]

I thought the test using strips is quite accurate

 

[Six feet down]

Other method is the bloodtest.

 

[blackhawk2000]

I added 0.5 gram to 1 litre distilled water, making the ppm equal to 500 ppm.

I added 2 ml of the above to 250 ml distilled water in a fresh container, therefore ppm is now 4 ppm.

This has given a good colour using API test.

Does this sound correct and pure? Thanks