what kind of small fishes do saltwater jellyfish eat?

Virtually anything they can catch. However if you are planning on keeping them then you'll want to feed them something else such as brine shrimp.

Plankton are drifting organisms that inhabit the water column of oceans, seas, and bodies of fresh water. They are widely considered to be one of the most important organisms on Earth, due to their food supply they provide to most aquatic life.

Jellyfish are marine invertebrates belonging to the Scyphozoan class, and in turn the phylum Cnidaria. The body of an adult jellyfish is composed of a bell-shaped, jellylike substance enclosing its internal structure, from which the creature's tentacles suspend. Each tentacle is covered with stinging cells (cnidocytes) that can sting or kill other animals: most jellyfish use them to secure prey or as a defense mechanism. Others, such as Rhizostomae, do not have tentacles at all. To compensate for its lack of basic sensory organs and a brain, the jellyfish exploits its nervous system and rhopalia to perceive stimuli, such as light or odor, and orchestrate expedient responses. In its adult form, it is composed of 94–98% water and can be found in every ocean in the world.

Most jellyfish are passive drifters that feed on small fish and zooplankton that become caught in their tentacles. Jellyfish have an incomplete digestive system, meaning that the same orifice is used for both food intake and waste expulsion. They are made up of a layer of epidermis, gastrodermis, and a thick jellylike layer called mesoglea that separates the epidermis from the gastrodermis.

Their shape is not hydrodynamic, which makes them slow swimmers but this is little hinderance as they feed on plankton, needing only to drift slowly through the water. It is more important for them that their movements create a current where the water (which contains their food) is being forced within reach of their tentacles. They accomplish this by rhythmically opening and closing their bell-like body.

Since jellyfish do not biologically qualify as actual "fish", the term "jellyfish" is considered a misnomer by some, who instead employ the names "jellies" or "sea jellies". The name "jellyfish" is also often used to denote either Hydrozoa or the box jellyfish, Cubozoa. The class name Scyphozoa comes from the Greek word skyphos, denoting a kind of drinking cup and alluding to the cup shape of the animal.

observed grouper, Epinephelus summana. The minimum tank is ideally one hundred eighty gallons yet they seem to be a smaller and lazier grouper that could extra healthful wonderful in a one hundred gallon in case you do no longer inventory it with different fish and do regularly occurring water differences. those men will devour very very nearly something and actually enjoy occasional stay snacks.

2 words: Brine Shrimp, Go to you local pet store of Fish store.

anything organic, it'll eat.

they don't eat anything bigger than them..

plankton?