Marine Ammonia
24
• Press
Zero
. The display will show “‑0.0‑” when the meter is zeroed and ready for measurement.
• Remove the cuvette.
• Unscrew the cuvette cap. Using scissors, open one packet of
HI784C‑0
along the dotted line. Push the two corners together to make a spout.
Add the content of the packet to the cuvette.
• Replace the plastic stopper and the cap. Shake gently to dissolve the
powder (30 seconds).
• Insert the cuvette into the holder and ensure that the notch on the cap is positioned securely in the groove.
• Press
Read
. The display will show a 15 minute countdown prior to the measurement. To skip the timer,
press
Read
. When the timer ends, the meter will perform the reading. The instrument displays the
ammonia/ammonium concentration in
ppm NH
3
.
To calculate the unionized ammonia (NH
3
) concentration, use the conversion table.
CALCULATING UNIONIZED TOXIC AMMONIA
This method measures NH
3
/ NH
4
+
.
To determine the toxic NH
3
portion, use the table to determine the percentage of toxic NH
3
. Levels of toxic NH
3
greater than 0.01 ppm have a negative effect on fish. Multiply total ammonia (NH
3
/ NH
4
+
) by the percent
unionized ammonia from the table to determine unionized toxic ammonia.
Example
: pH 8.0, Temperature: 24 °C (75 °F), NH
3
/ NH
4
+
1.00 ppm
Unionized toxic ammonia: 1.00 ppm x (5.0 ÷ 100 )= 0.05 ppm