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Tips for an Accurate Measurement
• Ensure the sample does not contain any debris.
• Hold dropper bottles completely vertically and squeeze slowly
to ensure correct drop size.
• Whenever the cuvette is placed into the checker, it must be dry
outside and free of fingerprints, oil and dirt.
• Wipe the cuvette thoroughly with
HI731318
microfiber
cleaning cloth or a lint-free cloth prior to insertion.
• Shaking the cuvette can generate bubbles, causing higher
readings. To obtain accurate measurements, remove such
bubbles by swirling or by gently tapping the cuvette.
• Do not let the reacted sample stand too long after reagent has
been added, as accuracy will be affected.
• Discard the sample immediately after the reading has been
taken or the glass might become permanently stained.
• Prepare sample cuvette immediately after collecting sample from tank. Ammonia
is volatile and will dissipate if stored in a bottle before analysis, causing low
measurements.
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
Percentage of Unionized Ammonia (
NH
3
)
pH
21 °C (70 °F)
24 °C (75 °F)
26 °C (79 °F)
29 °C (84 °F)
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
10mL
10mL
Battery Replacement
To save the battery, the checker shuts down after 10 minutes
of non-use.
A fresh battery lasts for a minimum of 5000 measurements.
When the battery is drained, the instrument displays “bAd”
then ”bAt”, and turns off.
To replace the battery, follow the next steps:
1. Press and hold the ON/OFF button to turn the checker off.
2. Turn the instrument upside down and use a screwdriver to
unfasten the screw and remove the battery cover.
3. Remove the old battery, replace it with a new 1.5V AAA
battery, inserting the negative end first.
4. Replace the battery cover, fasten and tighten the screw.
Accessories
Reagent Sets
HI784-25
Reagents for 25 Marine Ammonia tests
Other Accessories
HI784-11
Marine Ammonia certified standard kit
HI731315
Glass cuvette and cap for Checker
®
HC colorimeters (2 pcs.)
HI731318
Cloth for wiping cuvettes (4 pcs.)
HI740028P
1.5V AAA battery set (12 pcs.)
HI740157P
Transfer pipette (20 pcs.)
HI93703-50
Cuvette cleaning solution, 230 mL
Certification
All Hanna
®
instruments conform to the
CE European Directives.
Disposal of Electrical & Electronic Equipment.
The product
should not be treated as household waste. Instead, hand it over to
the appropriate collection point for the recycling of electrical and
electronic equipment, which will conserve natural resources.
HI784
Marine Ammonia (NH
3
/ NH
4
+
)
INSTRUCTION MANUAL
Disposal of waste batteries.
This product contains batteries, do not dispose of
them with other household waste. Hand them over to the appropriate collection
point for recycling.
Ensuring proper product and battery disposal prevents potential negative
consequences for the environment and human health. For more information, contact
your city, your local household waste disposal service, or the place of purchase.
Recommendations for Users
Before using this product, make sure it is entirely suitable for your specific
application and for the environment in which it is used. Any variation introduced
by the user to the supplied equipment may degrade the checker’s performance.
For your and the checker’s safety do not use or store it in hazardous environments.
Warranty
HI784
Checker
HC is warranted for a period of one year against defects in
workmanship and materials when used for its intended purpose and maintained
according to instructions. This warranty is limited to repair or replacement
free of charge. Damage due to accidents, misuse, tampering, or lack of
prescribed maintenance is not covered. If service is required, contact your local
Hanna Instruments
®
office. If under warranty, report the model number, date of
purchase, serial number, and the nature of the problem. If the repair is not covered
by the warranty, you will be notified of the charges incurred. If the checker is to be
returned to Hanna Instruments, first obtain a Returned Goods Authorization (RGA)
number from the Technical Service department and then send it with shipping
costs prepaid. When shipping any product, make sure it is properly packaged for
complete protection.
Hanna Instruments reserves the right to modify the design, construction, or
appearance of its products without advance notice.
All rights are reserved. Reproduction in whole or in part is prohibited without the
written consent of the copyright owner, Hanna Instruments Inc., Woonsocket,
Rhode Island, 02895, USA.
IST784 02/22