For the purposes of this course, we recommend that you store algal collections in the glass-door refrigerator in the teaching lab as soon as possible after sampling, in lieu of adding chemical preservatives. We have found that most algal forms will survive long enough to complete projects within the scope of a semester, and you will not be exposed to toxic preservatives.
Cheesecloth works well to filter zooplankton.
The rest of this document provides preservation information that you may find useful outside this class. Storage periods require addition of chemicals that reduce bacterial activity and autolysis of algal cells. The discussion below is based on our personal experience in use of these preservatives. The single best preservative, in terms of cell structure retention, is buffered glutaraldehyde. It is not desirable to filter glutaraldehyde because it is highly irritating to mucous membranes.