Upon receiving, loosen cap and aerate culture with a clean
should be maintained in diffuse or indirect light at temperatures from 65 to 75
°F (18 to 24 °C).
Culture Daphnia in an aquarium or vessel filled with filtered spring/pond water or aged tap water. Suggested minimum volume is one to two liters.
Daphnia can be maintained using one or a combination of the following methods:
(1) Two or three times weekly exchange 50 to 100 mL of water from the Daphnia culture with an equal volume from a rich culture of a unicellular, non-filamentous alga such as Chlorella.
(2) Mix one-fourth of a mashed, hard-boiled egg yolk in 500 mL of water and let it stand for one to two days to permit bacterial growth and then exchange equal volumes of culture water and suspension as above.
(3) Prepare a yeast suspension by adding a pinch of active dry yeast and
a pinch of sucrose to warm water, let stand an hour or two and add one to
several pipets full to the Daphnia culture. Both egg yolk and yeast
suspensions should be added in quantities sufficient to just cloud the culture
water, the Daphnia should be able to clear the water within several hours
to a day. Periodically supplement the Daphnia culture with several
milliliters of a mineral supplement (such as Knop's solution).