25
Marine Calcium
Percentage of Unionized Ammonia (NH
3
)
pH
21 °C (70 °F)
24 °C (75 °F)
26 °C (79 °F)
29 °C (84 °F)
7.4
1.1
1.3
1.5
1.9
7.6
1.7
2.1
2.4
2.9
7.8
2.6
3.2
3.7
4.5
8.0
4.1
5.0
5.8
7.0
8.2
6.3
7.7
8.8
11
8.4
9.7
12
13
16
8.6
15
17
20
23
8.8
21
25
28
32
7.4. MARINE CALCIUM
REQUIRED REAGENTS
Code
Description
Quantity
HI7581
Marine Calcium Reagent A
1 mL
HI7582
Marine Calcium Reagent B
1 packet
REAGENT SETS
HI758‑26
Marine Calcium Reagents
25 tests
For other accessories see Accessories section.
MEASUREMENT PROCEDURE
Select the
Calcium Marine
method using the procedure described in Method Selection section.
Note
: If tutorial mode is disabled, follow the measurement procedure below. If the tutorial
mode is enabled, press
Measure
and follow the messages on the screen.
• Use a 1 mL syringe and add 1 mL of
HI7581
Marine Calcium Reagent A to the sample.
• Use the plastic pipette to fill the cuvette to the 10 mL mark with deionized water.
Use Type 2 grade water or water that has electrical conductivity
≤ 1 µS/cm. For best results, measure the deionized water with a clean,
rinsed 10 mL syringe.
• Replace the plastic stopper and the cap. Invert 3 to 5 times to mix.
• Insert the cuvette into the holder and ensure that the notch on the cap
is positioned securely in the groove.
1 mL
10 mL