ppm
From The Aquarium Wiki
Parts Per Million (PPM)
Often used to describe the concentration of chemicals dissolved in water.
This measurement of unit is mainly used in the USA.
ppm = mg/l, equals ml/l. So 4 ppm equals 4 mg/l or 4ml/l
Parts Per Million (PPM)
Often used to describe the concentration of chemicals dissolved in water.
This measurement of unit is mainly used in the USA.
ppm = mg/l, equals ml/l. So 4 ppm equals 4 mg/l or 4ml/l