LaMotte SMART Spectro Spectrophotometer User Manual

Page 67

APPLICATION:

Low concentrations of ammonia in fresh, brackish and salt

water; fresh and salt water aquariums.

RANGE:

0.00–1.00 ppm Ammonia-Nitrogen

MDL:

0.02 ppm Fresh Waer

0.10 ppm Salt Water

METHOD:

Salicylate and ammonia react at high pH in the presence

of a chlorine donor and an iron catalyst to form a blue

indophenol dye, the concentration of which is proportional

to the ammonia concentration in the sample.

SAMPLE HANDLE &

PRESERVATION:

Ammonia solutions tend to be unstable and should be

analyzed immediately. Samples may be stored for 24

hours at 4°C or 28 days at –20°C.

INTERFERENCES:

There are few interferences in most natural waters. High

concentrations of reducing agents, such as hydrazine,

react with the chlorine donor and can result in negative

interferences. Color and turbidity can also interfere.

AMMONIA-NITROGEN, Low Range

SMART Spectro Test Procedures 2.11

Test P

rocedures