Drawing the sample into the pipet using a pump or a bulb past the calibration mark of your intended sample. Release excess sample with the thumb. Always run smaller sample first. Next, open lid and pull filter out and put into petri dish with nutrient broth ampoule. Put next filter into aseptic system.
Count samples only if the blank is completely free of colonies .
Multiply by the dilution factor before recording. Then turn them right-side up. Cap bottle under water to ensure no oxygen has been introduced. If bubbles are present, repeat procedure. Shake after adding both.