Preservation and storage of water samples. • Samples for phytoplankton analysis should be preserved immediately after collection by adding Lugol’s Iodine Solution. •  Lugol’s Iodine Solution should be added until the sample is the colour of weak tea/light beer (dark yellow/light brown) after preservation. The sample should be agitated during addition of the Lugol’s Solution to ensure thorough … Continue reading Lugol’s Iodine Solution