i have a feeling my elos nitrate kit is bad for sure....tested it with 4 kits total
elos (year old or so) 10-20ppm
API (year old or so) 0
API (brand new) 0
API (5 months old) 0
tested it with my bros, mine, and my sisters kits and for sure there all 0 other then my elos so has to be a bad one...