Max Size: 8cm

Ornate Rainbowfish (Rhadinocentrus ornatus)

Ornate Rainbowfish are relatively popular amongst hobbyists as they are very peaceful, a decent size and reasonably hardy as they can adapt to various water conditions.

You can keep Ornate Rainbowfish in a well-planted species only aquarium, or you can house them with other small and non-aggressive fish in a community aquarium. However, it would be better if you did not keep them with boisterous or aggressive species as they will have difficulty fending for themselves.

Like other Rainbowfish, these can be pretty skittish and do much better when kept in a shoal of 6 or more as this will encourage the males to display their best colours when they are in the company of their species.

The Ornate Rainbowfish has a small, slender and somewhat elongated body that is semi-transparent, and they possess two rows of black scales along the middle of their flanks. In addition, they have pearlescent scales above the lateral line and just below the dorsal fin; these can be either metallic light blue or red.

These Rainbowfish have two dorsal fins that are narrowly separated, and the first dorsal fin is significantly smaller than the second. The dorsal, caudal and anal fins are generally blue, although they can sometimes be red and have black edges; it depends on which area they originate.

The semi-transparent body may have pink, blue or red hues, with the dark edges of the scales creating a network-like pattern which they can also have on their two mid-lateral dark stripes. In addition, they have neon blue iridescent patches on their backs and their nape.

Quick Facts
Scientific NameRhadinocentrus ornatus
Other Namessoft-spined sunfish
Aquarium LevelMiddle
DifficultyBeginner - Intermediate
Best kept asGroups 6+
Lifespan3 - 5 years
Water Parameters
Water TypeFreshwater
PH5.5 - 7.5
GH10 - 20
68 - 82℉
20 - 27.8℃

Photos of the Ornate Rainbowfish

Ornate Rainbowfish
Ornate Rainbowfish

Natural Habitat

Ornate Rainbowfish are endemic to northern New South Wales and southern Queensland in Australia. These Rainbowfish can be found in various habitats containing sandy tannin-stained waters with little to no flow from coastal streams to stagnant pools or streams, as well as creeks, backwaters of larger streams, dune lakes and ponds. Ornate Rainbowfish prefer hanging out in small schools with their kind as well as other species under the shelter of branches, submerged logs, reeds, grassy banks and lily roots.

What to feed the Ornate Rainbowfish

The Ornate Rainbowfish is not fussy when it comes to their food. High-quality flakes, micropellets, green flakes and granules should be the staple of their diet. However, like most fish, regular feedings of live, freeze-dried or frozen foods such as mosquito larvae, bloodworm, daphnia, brine shrimp and tubifex will help your fish present their best colours and best health.

How to sex the Ornate Rainbowfish

It is relatively simple to differentiate between the male and the female Ornate Rainbowfish. Males are more vibrantly coloured than females and have a long second ray in the second dorsal fin and an elongated anal fin. When in breeding conditions, the males also develop a red stripe that runs from the snout to the second dorsal fin. In contrast, females have shorter fins, have duller colouration, and are usually slightly smaller than males.

How to breed the Ornate Rainbowfish

Ornate Rainbowfish are not incredibly hard to breed; raising the fry could prove quite tricky.

If kept in a community aquarium, the Rainbowfish will require a separate breeding tank. The breeding tank will need to be heavily planted with fine-leaved plants; however, spawning mops can be used as an alternative to plants if these are unavailable.

The temperature needs to be lowered by a few degrees compared to what they usually have, and the water needs to be slightly hard and alkaline. A small air-powered filter is also advisable to provide adequate flow and oxygenation needed.

You will need to condition the fish with protein-rich frozen or live foods for a couple of weeks before spawning. You will know when the fish are ready to spawn as the males will start to display to each other, and the females will become noticeably plumper. At this point, you should pick the healthiest and best-coloured fish and place them in the breeding tank.

The mating pair will produce for several days. In this time, the male will lead the female to a spawning site where the female will lay bunches of eggs and attach them to the available surfaces of plants or equivalent by a tiny thread, and the male will fertilise them. This process will continue until the female has run out of eggs.

You should check the spawning mediums for eggs several times a day, then remove them and place them into a separate grow-out tank to avoid being consumed by the parents; although this is unlikely, this is best for maximum results.

After around 7 -10 days, the eggs will hatch into small fry, and you will need to provide them with freshly hatched baby brine shrimp, microworms or powdered fry food for a couple of weeks until they are big enough to accept bigger food.

Other Rainbowfish of interest

Banded Rainbowfish(Melanotaenia trifasciata)
Boesemans Rainbowfish(Melanotaenia Boesemani)
Celebes Rainbowfish(Marosatherina ladigesi)
Dwarf Neon Rainbowfish(Melanotaenia praecox)
Forktail Blue Eye Rainbowfish(Pseudomugil furcatus)
Honey Blue Eye Rainbowfish(Pseudomugil Mellis)
View all Rainbowfish
Date Added: 25/01/2022 13:33:28 - Updated: 25/01/2022 15:05:32