The Green Fire Tetra
by Joe Kaznica
First published in Gravel Gossip, Diamond State Aquarium Society
The Green Fire Tetra, also known as Rathbun's Bloodfin, is a true gem of the small toy
fish world that can be often overlooked. Indeed, I walked past this fish in the aquarium
shop tanks, but my wife, Sandy, recognized it for the special species that it is. In the
dealer's tank it was a small green gray fish showing a little bit of red towards the tail.
In a planted tank, it can only be described as a living jewel. This fish is small with a
maximum size of two inches. Its special fascination is that the fish's color changes and
evolves with time. The body of the male is a metallic blue green, and the anal fin and
lower rear of the body is red. As the male matures the tips of his pelvic and anal fins
turn a brilliant white. As he matures further, the edges of the lobes of his tail turn
white. The base of the tail is red and spreads over the remainder of the tail as he ages.
When the male displays for spawning or dominance, the base of his anal and dorsal fins
turn a deep black green color. The female has a more heavy body, and she is more of a
metallic greenish blue in color. She has a hi-light of blue along her lateral line. She
also has the red that the male has, but her fins are clear.
Eigenmann first described the Green Fire Tetra in 1907. It comes from the Rio Paraguay
in South America. The habitat of this fish is very varied depending on the season of the
year. Because of the varied habitat, this species does very well in average type
conditions. A temperature of 73F degrees, neutral pH, and medium hardness. It will readily
eat any good fish food. By personal experience it does not like extremes of conditions and
unlike most tetras it does not do well at low pH. It can be kept in a community tank with
other peaceful fishes, and it greatly appreciates floating plants in the tank where it can
swim in and out of these plants. I keep about a dozen in a school with a few more females
than males. Oddly when schooling the males and females tend to keep within their own sex
within the school.
This species is a group spawner. I place three pairs in a ten-gallon tank with floating
plants and a wad of java moss onto which they will lay their eggs. I cover the bottom of
the tank with marbles so when the eggs fall through the java moss, they also fall through
the marbles, and the parents cannot get at them. The breeding temperature is 78F degrees,
neutral pH, and hardness of about 60 ppm. Although all of the fish spawn in this set up,
the largest female, along with the most dominant male, lays most of the eggs. After
spawning, remove the adults. You will see fry in about five days. Feeding liquid food for
a few days along with baby brine shrimp easily raises them. The only negative thing I can
say about this species is that they mature very slowly. It takes about five months for the
males to develop their white fins, and fully mature colors may take sixteen months. Please
believe me when I say that to see this beautiful fish at maturity is really worth the
wait. All good things come to those who wait!