Species group: Jellyfish
Other common names: Spotted Jellyfish, Floating Bell Jellyfish
Scientific name: Phyllorhiza punctata
Much admired by marine aquarists for its attractive light-reflective spots, this very common jellyfish is often collected for the pet trade. The Australian Spotted Jellyfish may fare well in captivity, but does grow very large.
The Australian Spotted Jellyfish ranges through the Indo-Pacific Region to Australia, and has been introduced (via hitchhiking polyps and ballast water) to Hawaii, the southeastern USA, Caribbean Sea, Gulf of Mexico, and Brazil. It occurs in coastal waters, tidal rivers, bays and salt marshes.
Appearance / health:
The clear to brownish body sports light-reflective white spots, and may reach 50-70 cm. (20-27 in) in diameter.
Small Australian Spotted Jellyfish have been successfully kept, but are considered by most as difficult to maintain. Poor water quality, starvation, and inappropriate temperatures and aquarium design (see below) are the most common causes of fatalities. Jellyfishes cannot tolerate copper-based medications, ammonia, or nitrites.
Behavior / temperament:
The Australian Spotted Jellyfish is a strong swimmer and remains continually in motion. Its sting is considered only mildly-annoying, but the possibility of individual sensitivities or serious allergic reactions must be considered. Jellyfishes are best housed only with others of their kind, as their stings can injure or kill various invertebrates and fishes.
Australian Spotted Jellyfish should be kept in a Kriesel, which is a circular aquarium specifically designed for jellyfish. Kriesels are equipped with a filtration and pump system that creates the type of current flow that is essential for keeping jellyfish in motion and feeding in the water column. The tank should be free of decorations, as jellyfish easily become entangled in coral and other structures.
The following water quality parameters are critical to long-term health:
Specific Gravity (Salinity): 1.015-1.020; Temperature: 24-26 C (75-78 F); pH: 8.1-8.4; Alkalinity 8-12 dKH; Ammonia/Nitrites: 0; Nitrates: below 5 mg/l. Calcium, iodine and other trace elements should be added as suggested by the product manufacturer.
Australian Spotted Jellyfish should be provided multiple daily feedings of newly-hatched brine shrimp and, if available, zooplankton. Brine shrimp should be nutritionally enriched with a commercial algae-based diet designed for that purpose (i.e. Selco) beforehand. Australian Spotted Jellyfish may also accept liquid plankton formulas, commercial dry jellyfish diets, small fish, and frozen krill.
Australian Spotted Jellyfish reproduce sexually and asexually, going through several stages that differ greatly in appearance and lifestyle before becoming an adult, or medusa. Successful breeding is now routine in several public aquariums.
Written by Frank Indiviglio