sansouci01
Aquarium Advice FINatic
when I check the color of my test water, I use a sheet of white paper instead of holding it against the color chart paper. My question is, do you hold it right up against the paper or a little bit off the paper. big difference in the color from one method to the other. my nitrates read 20ppm when I hold it close to the paper. right up against the paper it reads 50ppm ( color looks darker )