They feed on crustaceans while swimming with their mouths open.
There have been no reports on feeding in the cyematids.

Because there is not enough light for photosynthesis, much less energy is available to support animal life. Bacteria and detritus ( pieces of dead plants and animals that slowly settle to the bottom ) are the primary sources of food for animals like jellyfish that are confined to this zone. Other animals,including squids,fishes,and shrimps can move up and down through the water column,and have a wider range of food available to them.

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