Just take a look at this little beauty, discovered on sale at an Essex shop. Nathan Hill has the lowdown on this fabulous tetra, which we hope may soon become more commonly available in the hobby.
Common name: Imperial blue rainbow tetra. Sometimes known as Hyphessobrycon sp. Red-Blue and the Blue Peru redfin tetra
Scientific name: Hyphessobrycon sp.
Origin: The fish shown is a captive bred example, but originally they come from Peru.
Size: Unknown full adult potential.
Diet: Like other Hyphessobrycon, they feed readily on dried foods, but will also be happy to take aquatic invertebrates.
Water: Although the fish here is being kept in harder, alkaline water, expect them to thrive in clean, soft acidic water with a pH of around 6.5. Temperature range of 24-25°C is preferred.
Aquarium: Many Hyphessobrycon appreciate tanks with a flow of water, so provide regions where pumps create ample movement. Plants will be used as cover, and should be provided. These fish will not fare well in low numbers, and would be liklier to retain their shoaling instinct if kept in numbers of 12 or more.
Notes: These tetras have been known from around 2006 when they were first imported from Peru.
Many fish that are traded under the Red-blue moniker are subtly different from each other — some having more green, others having yellow-orange fins rather than red.
Either way, these are stunning fish and show a great deal of potential for bringing colour to any tetra-based aquarium.
The individuals shown were at Wayside Aquatics in Essex, and brought in as tank bred specimens and not wild caught.
Although young, a myriad of colours were already forming on them and they were starting to take the metallic blue tint that adults carry.
Sexing: Expect plumpness of females, and potentially tiny hooks on the anal fins of males.
Availability: These are not a commonly found fish, and the fish pictured are the first that the author has seen in the flesh. With Czech and German programs we can hope that these fish become more prolific in the hobby, but it is unlikely that they will become cheaper as a result.
Price: These retailed at £3.95 each during a recent visit.
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