The Bloodfin tetra is easily recognized on its colourful fins. The caudal fin, anal fin, ventral fins and dorsal fin are of a vivid red colour that contrasts brightly against the silvery body. This fish species is however not only appreciated for its beauty; it is also an active and sturdy fish that can live for over 10 years in captivity. The Bloodfin tetra is recommended for beginners and is an alternative to the more famous Neon tetra.
Aphyocharax anisitsi, Bloodfin tetra : aquarium - FishBase
This Tetra originates in South America, namely the Amazon river - in the inflow Maderia which means the natural environment for these fish is a tropical freshwater aquarium, preferably biotope. Speaking generally these tetras aren't very demanding, nor hard to keep, however they require stable conditions with general water hardness (dGH) of 10° and a little alkaline water with pH slightly over 7 (7.1 or 7.2 is just fine). I've kept Glass bloodfin tetras in acidid water with very negative results, they started turning white and kept dying slowly. When it comes to temperature, these tetras are very adaptable which means anything between 22 and 28°C is OK (72-82°F). As the note regarding biotope implies, Glass bloodfins prefer tanks with hiding places as well as with places where it's possible to swim freely as they're little athletes that love to chase each other, but also love to stay in one place almost 12 hours a day - this also depends on their company, if there's a fish that keeps chasing them, naturally these tetras won't stay in one position. As with other Tetras, Glass bloodfins aren't demanding in terms of space as they group and prefer to stay in shoals as much as possible - all in all, a 100 liter tank can house even 50 of these small creatures and still such a tank won't be overcrowded. Never keep one or two of these tetras (it's similar with all tetras) as they will be shy and won't come out of hiding places as often as expected. We always recommend to keep at least 6 specimens of each specie, however 10 or 20 of same species is more than welcome! As mentioned previously, these fish don't require much space, however housing them in undersized tanks isn't wise as they need space - especially length - for chasing each other. Glass bloodfins aren't aggressive, however they chase each other and play together often which means they really need open spaces without decorations and sharp edges, otherwise they may hit such objects which usually leads to injuries including losing one or both eyes. A 40 liter or smaller tank isn't recommended - use a 80 liter display tank at least.
Bloodfin Tetra | Tim's Tropical Fish
Glass Bloodfins are a beautiful fish that do well in either a tank by themselves or in a community tank with other peaceful fishes. The clear body is an interesting feature, and while not very flashy, these fish are always worth keeping.
Bloodfin Tetra - Fish Lore Aquarium Fish Forum