Hach-Lange BODTRACK II User Manual - Manual (Page 15)

Hach GGA (glucose/glutamic acid) procedure
Items to collect:
• BODTrak II bottle
• Graduated cylinder
• Volumetric pipet and pipet filler
• Tensette
® pipet and pipet tips
• Wash water bottle
• Ampule breaker
Required reagents:
• Deionized water
• Hach GGA solution
• Nutrient buffer pillow (1x)
Before a test:
Use Hach BOD Standard Solution Ampules for Manometric Method (3000 mg/L
Glucose, 3000 mg/L Glutamic acid).
Always prepare the seed blank before the GGA samples. Use the same amount
of seed for all GGA samples and seed blank.
Refer to section Special considerations on page 18 for special considerations.
Use the correct volumes for the BOD range as shown in Table 5 .
Prepare seed blank: Use steps 1 and 3 to 7.
Prepare sample: Use steps 1 to 7.
Table 5 GGA sample volumes
BOD range
(mg/L)
GGA volume
(mL) Seed volume
(mL) Final volume
(mL)
0 to 350 8.0 10 to 35 160
Note: If the seed strength is unknown, use 20 mL. Adjust the seed volume as
necessary to achieve optimum GGA results. Use the same amount of seed for all
GGA samples and seed blanks.
1. Add approximately
30 mL of deionized
water to a 200-mL
graduated cylinder. 2. Use a volumetric
pipet to move 8.0 mL of
Hach GGA solution to
the graduated cylinder.
Note: Skip this step
when the seed blank is
prepared. 3. Add the contents of
1 nutrient buffer pillow
to the graduated
cylinder.
4. Use a tensette pipet
to add the correct
quantity of seed to the
graduated cylinder
(
Table 5 ).
5. Use a deionized
water wash bottle to
dilute the sample to
160 mL. 6. Move the prepared
sample from the
graduated cylinder to a
BODTrak II bottle.
Continue to
Completion
steps for all procedures
on page 15.
Note: For additional
GGA samples, repeat
steps 1 to 6.
English 13