Gertrude's Spotted Blue Eye Rainbowfish (Pseudomugil gertrudae)

Imported European Fish

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This tiny but colorful fish is native to Papua New Guinea and Northern Australia. Pseudomugil gertrudae, or Gertrude's Spotted Blue Eye Rainbowfish, was named for the wife of Dr. Hugo Merton, a German naturalist who visited the Aru Islands, eastern Indonesia, in 1907 and 1908. As with almost all other fish, males of the species are more colorful and intricately patterned than are the females. Male Pseudomugil gertrudae also have longer finnage, especially on their pectoral fins which arch up and then down as with other dwarf rainbowfish.

Completely peaceful but sometimes prone to jumping (especially when startled), these fish do best in groups of eight or more. They are a shoaling species, choosing to hang out in a large group but not necessarily moving in a unified direction, even when under stress or threat. Because these are dwarf rainbowfish, they are extremely small and so keeping a small clan of them in a 10-gallon nano aquarium is perfectly acceptable, however you should be aware that these fish are diminutive in size and in courage as well. They need cover, peace and privacy to unwind so placing them into a heavily planted nano aquarium will make them happy and will go far in mimicking their natural environment. Please do not attempt to keep these fish in an aquarium with other larger, aggressive fish.

Gertrude's Spotted Blue Eye Rainbowfish feed readily on fish flakes, live food that is small as well as frozen food such as baby brine shrimp and daphnia. In the wild Pseudomugil gertrudae feeds primarily on tiny crustaceans and insects on leaves, on the bottom and in the water column; feeding these wonderful nano fish a nutritious food should be easy but make sure that it is small enough for the little fellows to enjoy.

This fish is often found in tannin-stained waters in the wild with hardness quite low and, in some cases, has no dissolved solids not unlike rainwater. They prefer inhabiting waters in the wild with floating vegetation, probably to avoid being caught and eaten by birds and other predators swooping in from above. These fish should not be placed into an immature aquarium as they do not tolerate wild water parameter swings, and they much prefer well-oxygenated water.

This is a tiny fish, with males and females never quite reaching two inches in length. In captivity, feeding them on live and frozen food in a heavily planted aquarium with somewhat diffuse lighting should eventually cause breeding to occur. These fish prefer to lay eggs in moss such as Flame Moss, Weeping Moss and so on. They prefer temperatures between 70 F and 82 F and will tolerate a water pH range of 5 to 7.5, and water hardness anywhere from 80 to 210 ppm. If this fish is kept in a community setting, please ensure they are receiving enough food because they are easily frightened off and outcompeted. This fish does not ship individually bagged.

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Imported European Fish

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