4.1 Calcium Carbonate (CaCO₃) buffered formalin (3 to 5 %) can be used as a permanent preservative for zooplankton. Lugol’s iodine solution can be used to preserve zooplankton for up to one year. Thirty percent ethanol, 30 % glutaraldehyde, or 25 % vinegar (can use 3 % acetic acid solution) can be used for more temporary storage and preservation of zooplankton samples. A 25 % vinegar solution is preferred to preserve soft-bodied planktonic coelenterates.

1.1 This practice describes the proper procedures for preserving zooplankton samples with either formaldehyde, ethanol, glutaraldehyde, Lugol’s iodine solution, or vinegar (acetic acid).

1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.