This is the fluorometer. Sea water flows constantly through the meter. Twice a day, a water sample is collected and run through a vacuum flask to extract chlorophyll. The chlorophyll is collected on a piece of filter paper perched atop the vacuum flask. The filter paper is removed and placed in a cuvette (small test tube), stored in acetone, then refrigerated. Back on land, the chlorophll cuvette will be put in a spectrophometer and read.