The Purple Firefish, also known as the Decorated Firefish, Purple Dartfish, Decorated Dartfish, or Flame Firefish, was first discovered in the Indo-west-Pacific Ocean in 1973 by Randall and Allen. The colorful body base is varied degrees of yellow to white, and deep shades of purple which begin at the head and ends with maroon-tipped fins.
It requires a 10 gallon or larger aquarium with plenty of loose coral rubble as part of the aquascape, and a tight-fitting lid to prevent it from jumping out of the tank. It will rarely become aggressive towards other fish, but is territorial, and will fight with its own kind unless they are a mated pair.
The Purple Firefish will feed mostly on prey suspended in the water column, but will pick food off the substrate. Its varied diet should consist of chopped or shaved seafood, frozen food preparations for carnivores, vitamin-enriched brine shrimp, and mysid shrimp. The vibrant coloring will fade if not fed a vitamin-enriched diet
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The Firefish Goby is also known as the Firefish, Fire Goby, Magnificent Dartfish, or Fire Dartfish. Its head is yellow, the anterior portion of the body is white, and the posterior portion a pinkish to orangish red. The dorsal, anal, and caudal fins are highlighted in black. In the wild, Firefish Gobies are usually found in groups hovering over the reef, harvesting planktonic food that drifts by in the current. Each Firefish Goby will have a "bolt-hole," which it quickly ducks into when threatened.
Firefish Goby are a sweet-tempered fish with lots of personality, making them one of the more popular fish in the marine hobby. Because of their small size, they make a great addition to the smaller reef system. There are two, closely-related fish, the Flame (Purple) Firefish, N. decora and the rarely seen N. helfrichi.
They will try to jump out of the tank, especially if stressed, so the Firefish Goby should be housed in a 10 gallon or larger tank with a lid. Hobbyists who use a halide system with an open top should construct a Plexiglas "edge" around the trim, at least 10" tall. It is generally not aggressive towards other fish except those of its own species; a mated pair can live peacefully. The Firefish Goby prefers moderate lighting conditions, several hiding places to duck into when threatened, and a moderate current passing over the reef.
Along with algae and zooplankton growing in the tank, the diet of the Firefish Goby should consist of finely chopped small crustaceans, vitamin-enriched brine fish (live or frozen), mysid shrimp, and prepared foods.
Both descriptions say they'll be agressive toward their own species, so i'd say no, don't add both to the tank.