The tiny Tetra from Rio, which has many names — Flame Fish, Flame Tetra, Red Tetra, Tetra From Rio, or Von Rio Tetra — is one of the most entrancingly beautiful of all aquarium fish, especially when in full breeding colors! This fish belongs to the family Characidae and comes from the environs of Rio de Janeiro in Brazil. It was first imported into Europe in 1920 and the US soon afterward. The body is elongated, slightly compressed, about 1 ½ inches long and shiny gray in color.
Its sides are bronze to red, and its back is brilliant red as are the majority of its fins. The anal fin has a black leading edge and tip.
The Male's Characteristics
The male is smaller and its anal fin is distinctly edged with black. Its body is somewhat pudgy, tapering to the tail, which expands into a considerable caudal fin. The colors, in prime conditions, are pearly lilac on the forward belly with yellow glints in an indistinct horizontal line to the tail. The lower abdomen and the anal, dorsal and caudal fins, rather than being exactly flame-colored, are suffused with flame, On each side of the forward part of the body are two dark spots, one behind the other, that look like smudges.
The two sexes are much alike, both in color and shape. The male has a tiny hook on his anal fin, which can catch on a fine mesh net. If this happens, great care must be taken not to break the hook off in the net, for he uses this hook in breeding to hold the female close to inseminate the eggs as the female deposits them on a fine leafed plant.
Without this hook, the fertility rate of the eggs will probably be quite low.
The Female's Characteristics
Many observe a point in the anal fin of the female, but this in not definitive or consistent from fish to fish. Further, there is a broad, black border to the anal fin of the male, this border either completely absent in the female or simply narrower and lighter in tone.
The region of the belly is thicker and rounder in the female, which makes them deeper in the body than the slimmer males. At breeding time the females will be very plump with eggs and the contrast between male and female even clearer when the male turns almost totally bright flame red!
The History of the Fish
At one time the popularity of this sturdy little Characin reached stellar proportions. Almost no community aquarium was complete without this fish. In the 1940s and 1950s, it was among the number one sellers of all Characins. One reason for this overwhelming popularity was its ability to survive in temperatures of as low as 64F and as high as 85F, preferring temperatures of around 72F. Before the days of affordable heating for the home aquarium, this went a long way towards making it the first choice as a first fish. Additional attributes are this fishes ability to eat almost anything and survive, it's extremely peaceful nature and its acceptance of very low light situations.
The Ease of Breeding
Another prime reason for its popularity was the ease in which it breeds. It breeds in a small tank, no particular need for fresh water; spawns up to 500 eggs and the young are quite hardy!
For some reason, this seemingly eternal community aquarium favorite waned in popularity over the last 3 decades and was almost rare at the turn of the millennium. Its popularity today is again growing, and the “Von Rio Tetra” can now be found in most tropical fish retailers from time to time.
For breeding proposed great care must be taken to find specimens which are the reddest in appearance and ones with good body shape along with the attributes described above. Due to its recent resurgence in popularity, there are many of these fish making it to market that are dull and misshapen, as time goes on, the lines will become more stable, and the “Flame” Tetra will return!
So simple is this fish to breed that it is recommended to beginners who are spawning egg-layers for the first time! The basic requirements for this species are a 10-gallon tank planted with thickets of small leaved plants and, if possible, Java Moss.
The temperature should be brought up to around 80F before introducing the well-conditioned female which has been kept in isolation from the male and fed live food for a week.
The Process of Breeding
The female should be introduced in the afternoon, followed by the male about 1 hour before dark. Breeding will probably take place soon after dawn of the next morning. After laying anywhere between 150 and 500 eggs, the parents will rest briefly and then begin the egg hunt, they must be removed at once! Eggs hatch in 24 – 48 hours, fry hang on plants and on the glass of the tank for about 2 days and are free swimming on the third day.
The fry should be fed infusoria the first week, later alternating with baby brine shrimp and commercial baby powdered food. They are very hardy in the third week, though they tend to stay towards the bottom of the tank and will devour almost anything. At the age of about 4 months they begin to look like their parents and are fully half grown! At 6 months they can be introduced into a community aquarium as a new shoal of fish.