Plankton net

A Plankton net is equipment used for collecting samples of plankton in standing bodies of water. It consists of a towing line and bridles, nylon mesh net, and a cod end. Plankton nets are considered one of the oldest, simplest and inexpensive methods of sampling plankton . The plankton net can be used for both vertical and horizontal sampling. It allows researchers to analyse plankton both quantitatively (cell density, cell colony or biomass) and qualitatively (e.g. Chlorophyll-a as a primary production of phytoplankton) in water samples from the environment.

Towing line and bridles

The towing line and bridle is the upper part of a plankton net and used to hold it. The towing lines connected to the triangle bridles are made of nylon rope and can be adjust to a level suitable for the user.

Nylon mesh net

The nylon mesh net is the middle part of the plankton net and is used to filter the plankton in the water sample in accordance with the size of the mesh. In addition, its funnel shape makes it possible to effectively capture plankton of various sizes. There are various mesh sizes for nets, depending on the target microorganism to be collected and the condition of the water body. The narrower the mesh size, the smaller the plankton in the water sample.

For example, in order to obtain small invertebrates measuring 50 to 1500 μm, a net mesh size between 25 and 50 μm diameter should be selected, which is sufficient to effectively filter only the target organism. However, in a eutrophic water condition, a plankton net with a mesh larger than 100 μm should be chosen to avoid clogging the net.

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