Hach-Lange BODTRAK II: Respirometric Biochemical Oxygen Demand (BOD) - Manual (Page 23)

BODTrak™ II procedures
23
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 seed strength is unknown, use 20 mL. Adjust seed volume as necessary to achieve
optimum GGA results. Use the same amount of seed for all GGA samples and seed blank.
1. Add approximately
30 mL of deionized water
to a 200 mL graduated
cylinder.
2. Use a volumetric pipet
to transfer 8.0 mL of Hach
GGA solution to the
graduated cylinder.
Note: Skip this step when
preparing the seed blank.
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. Dilute to the sample to
160 mL using a deionized
water wash bottle.
6. Transfer the prepared
sample from the
graduated cylinder to a
BODTrak II bottle.
Note: For additional GGA
samples, repeat steps 1 to 6.
7. Continue to the
completion steps for all
procedures ( section 5.5
on page 27 ).