Place a cover slip over a Neubauer haemocytometer. This is a special type of slide which is designed to act as a blood cell counting chamber.
Definitions
HAEMOCYTOMETER: This is a specialised microscope slide with one or two etched
grids and a thick coverslip. It
was originally designed to estimate concentrations of blood cells, but it
is now widely used in aquaculture to estimate concentrations of planktonic
organisms in small sub-samples of water.
There
are different types of haemocytometer, one of which is the Neubauer
haemocytometer used here.