Millennium Rainbowfish

Distribution:
   The Millennium Rainbowfish was described by Allen and Cross in 1980. It is only known to inhabit one lake in Irian Jaya (Indonesia).

Status:
  There is currently insufficient data to classify this species.

Description:
   The Millennium Rainbowfish is a slender and laterally compressed fish. Mature males have an arched back and narrow head. The eyes are large, the mouth is deeply forked, and two dorsal fins are present. At around three months of age, the males begin to develop a crimson body color that quickly deepens into a very intense blood-red. The body is accented with small, reflective silver scales which are spaced fairly evenly in rows (Unlike its similar looking relative, the Red Rainbowfish G. insicus whose silver scales are larger and appear more randomly).
   Males will display varying shades and intensities of red depending upon age, health, temperature, water quality, mood, and even rank in the school. Displaying males have the ability to “turn on” a brilliant neon orange stripe which serves as a breeding signal to females. Females and young males will be silvery brown. Some females will show faint vertical stripes around the middle of the body.

Size - Weight:
   Millennium Rainbowfish usually grow to be about 4 inches long (10cm).

Care and feeding:
   Millennium Rainbowfish are omnivores. Because diet can affect coloration greatly, special consideration should be given to formulating a healthy one. At least 50-75% of the diet should be a suitable flake or pellet food. The rest should be made up of a variety of live foods like bloodworms, tubifex worms, brine shrimp, and daphnia. Some good live food options include white worms, blood worms, or brine shrimp. If these are unavailable, frozen (defrosted) substitutes would be fine. Specially prepared commercial foods that are sold as 'color food' will contain dyes like carotene which is advantageous to enhance their color.
   The Millennium Rainbowfish is a high energy species which will swim laps around the aquarium tirelessly. As with many fish, Rainbowfish will do best and are most effectively displayed in tanks which simulate their natural habitat. The tank should be planted in the sides and back, with a stretch of open water in the middle. Bogwood and rockwork are both beautiful additions to the rainbowfish tank, but take care to arrange them so they won’t collapse amid all the activity.
   Due to the high activity level of this fish, a school can only be supported in a tank at least 30 inches long and at least 35 gallons in capacity. Eventually adults will need a larger tank, with 60 gallons or more being reasonable.The tank needs a tight cover to prevent jumps. The importance of partial water changes (25-50% per week) can not be overstated, as this is a deciding factor of body color. Slightly cooler temperatures, around 70 F (21 C) will make more of the males display brighter colors.

Water Region: Top, Middle, Bottom:
   Millennium Rainbowfish are usually found in the upper or middle region of the aquarium.

Acceptable Water Conditions:
   Temperature: 70 - 79° F (21 - 28° C)
   Hardness: 15 - 25 dGH
   Ph: 6.5 - 8.5

Social Behaviors:
   Millennium Rainbowfish require tank mates with a similar temperament and activity level. Choose similarly sized species that are playful and social but not aggressive. The easiest and one of the most visually impressive ways to do this is to form a geographical tank, and put the Millennium Rainbow in with its cousins.
   If the Millennium Rainbowfish is kept with both other males and females, the males will occupy themselves by displaying their brightest and best red colors and flaring their fins at each other. When males are displaying, you may notice some chasing between rainbowfish, but this is rarely a concern unless a fish is injured, has nowhere to hide, or is constantly harassed (usually a result of one of the first two).
  Millennium Rainbowfish are schooling fish and the ratio of males to females is very important to keep a reasonable peace among them. Although you can always keep single sex schools, the coloration is an entirely different experience in a breeding condition mixed sex school. Properly stocking rainbowfish is a little tricky so we include the following recommendation for stocking. Choose which type of school you want to keep and how many fish.

If you wish to keep…	School: MIXED SEX	School: MALES	School: FEMALES
5 rainbowfish	Do not mix sexes	5 males	5 females
6 rainbowfish	3 males+  3 females	6 males	6 females
7 rainbowfish	3 males + 4 females	7 males	7 females
8 rainbowfish	3 males + 5 females	8 males	8 females
9 rainbowfish	4 males + 5 females	9 males	9 females
10 rainbowfish	5 males + 5 females	10 males	10 females

Sexual Differences:
   Mature males will be redder in coloration and will have a highly arched back and narrow head.

Breeding/Reproduction:
   A breeding tank should be set up with a sponge filer and either many fine leaved plants or a spawning mop. A pair of healthy adult rainbowfish should be introduced. They should be conditioned with live foods and plant based foods. Remember, you are trying to emulate the bounty of the flood season so feed more and higher quality food than you normally would.
   After the female has produced eggs, the male will display an amazing show of intense colors and direct the female to the spawning site by doing a “headstand” over it, the pair will spawn, and then rest. The spawning mop or plants should be removed and replaced after the spawning or the eggs will be eaten. The fish will repeat this daily for about as long as you allow it, with steadily decreasing numbers of eggs produced. The parents should be removed when egg numbers fall or when the females show signs of fatigue.
   The fry will hatch after about a week and should be fed infusoria or a liquid fry food until they are able to eat small live foods. The fry are something of a challenge to raise until they are about two months old. The fry grow slowly and require clean water during the entire process.
   A problem to be aware of is crossbreeding. Rainbowfish in the wild will not breed with fish of another species, even when presented the opportunity to do so. But for some reason, rainbowfish of the Melanotaeniidae family in the aquarium will interbreed, often with undesirable results. Somehow the fry of mismatched parents lose most of their coloration. Since many of these species are rare, it is desirable to keep the bloodlines distinct, or risk losing the beautiful coloration that nature has taken thousands of years to develop. See an overview of how to breed Rainbowfish in Breeding Freshwater Fish.

Availability:
   The Millennium Rainbowfish, also sold as the Lake Ifaten Rainbowfish or Tami River Rainbowfish, is only imported by a handful of companies, making it extremely rare in captivity. The cost is anywhere from $5.00 - $15.00 USD per specimen.