Hach Eclox, User Manual

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10.7 Prepare the test suspension
Prepare the test suspension (stock suspension and Diluent mixture) by doing the
procedure in this section.
The Diluent is made according to ISO11348-3 and makes sure that the test is not
negatively affected by the presence of potassium (K+) and magnesia (Mg2+) ions in
the sample. The Diluent is a specially made non-toxic 2% sodium chloride (NaCl)
solution that contains potassium and magnesia ions.
The marine bacterium in the reagent requires the osmotic protection that is given by
the 2% NaCl in the Diluent. The potassium and magnesium in the Diluent stabilize
the light made over time. This stabilization helps keep high negative inhibitions from
getting with samples that contain potassium and magnesium ions.
Do not make Diluent or use substitutes.
1. Remove the Diluent
from the cool box.
Remove the cap from the
Diluent bottle.
2. Put 14.0 mL of Diluent at
refrigerator temperature in
the reaction vessel using
the pipette.
3. Remove the stock
suspension (rehydrated
reagent) from the cool box.
Remove the rubber
stopper from the reagent
bottle.
4. Set the 1.0-5.0 mL
pipette to 1.0 mL.
5. Put 1 mL of stock
suspension at refrigerator
temperature into a clean
reaction vessel using the
pipette.
6. Put the cap on the
reaction vessel and shake
to mix thoroughly.