Freshwater Jelly (Craspedacusta sowerbii)

Craspedacusta sowerbii is a freshwater hydrozoan with both polyp and medusa life stages. The medusae should be maintained in a kreisel, pseudokreisel, or any container that provides gentle circular flow to keep them suspended and prevent contact with surfaces. Small dishes or bowls with low flow can also be used for short-term maintenance or experiments. Traditional filtration devices such as airstones, sponge filters, or HOB filters should be avoided, as medusae are easily damaged. Craspedacusta sowerbii can be fed freshly hatched Artemia nauplii daily. Uneaten food and debris should be removed manually. Medusae are short-lived and typically persist for several weeks to months under laboratory conditions. The benthic polyp stage can be maintained separately in bare freshwater dishes or small containers with minimal flow. Polyps readily attach to glass, plastic, or stone substrates and are compatible with mechanical filtration.