before sorting, as much of the formalin as possible should be carefully decanten into a hazardous waste disposal container through a sieve so that no invertebrates are lost.
Note that it is possible to re-use the formalin at least once or twice, depending on the amount of organic material in the sample.
The sample should then be washed with tap water on the same size sieve used initially, and enough alcohol (70% isopropanol or ethanol) added to cover the sample and initiate the preservationof the sample.
This process should be done under a laboratory hood if possible so that the formalin fumes are properly vented.
The overall process ( formalin, washing, alcohol) results in invertebrates that are properly fixed and preserved, and can be stored indefinitely.
Further processing involves sorting the sample into appropriate taxonomic groups followed by identification to species or higher taxonomic levels. In many areas, the dominant invertebrates that occur in seagrasses are polychaete worms, crustaceans, and molluscs.
Hence, the initial sorting is made under low magnification (3x is typical) into these three taxonomic groups, which are in most cases readily identified