Emerald Eye Rasbora (Brevibora dorsiocellata)
Emerald Eye Rasboras are a peaceful and very hardy species of Rasbora, making them an ideal resident of the community aquarium.
These Rasboras have no particular demands when it comes to water chemistry; therefore, you can house them with most of the popular species in the hobby. These can include other small Cyprinids, Tetras, Livebearers and Dwarf Cichlids, as well as Catfish and Loaches.
Emerald Eye Rasboras are a tight shoaling fish that can be rather timid; therefore, it would be better if you kept them in groups of 10 or more individuals. Larger groups will help your fish feel more secure and result in a more effective, natural behaviour. In addition, males will also display their best colours as they compete with each other for female attention.
In the aquarium, the choice of decor is not as important as the water quality. However, these fish look especially effective in a well-planted aquarium with a dark substrate.
Emerald Eye Rasboras thrive in a natural-style set-up with a soft, sandy substrate and a few driftwood roots and branches placed to form plenty of shady areas. The addition of dried leaf litter further accentuates the natural feel. The leaves also offer even more cover for the fish as well as bringing on the growth of microbe colonies as decomposition occurs.
These microorganisms can provide an essential secondary food source for babies whilst the tannins and other chemicals released by the rotting leaves are beneficial for blackwater fish species.
Emerald Eye Rasboras prefer reasonably dim lighting, although this does hinder the use of some aquatic plants. However, Taxiphyllum, Cryptocoryne and Microsorum can all survive in such conditions.
The Emerald Eye Rasbora is an elongated fish with a pointed nose. Their base colour is a reflective, metallic silver; however, the fish can take on a yellowish hue under some lighting conditions, with a slight pink blush present in the central area of the body between the pelvic fins and the operculum. In addition, these fish sometimes display a thin olive gold-tinted parallel line from the operculum to the caudal peduncle under reflected light conditions. All their fins, except for the dorsal fin, are hyaline.
|Scientific Name||Brevibora dorsiocellata|
|Other Names||Eyespot Rasbora|
|Aquarium Level||Middle - Top|
|Difficulty||Beginner - Intermediate|
|Best kept as||Groups 10+|
|Lifespan||4 - 6 years|
|Temperature||73 - 79 ℉ (22.8 - 26.1 ℃)|
|PH||6.0 - 7.5|
|GH||3 - 12|
|TDS||18 - 179|
Natural Habitat of the Emerald Eye Rasbora
Emerald Eye Rasboras are endemic to the Greater Sunda and Peninsular Malaysia islands of Borneo and Sumatra in southern Thailand in southeast Asia. These fish inhabit gently flowing black water rivers and streams and are associated with old forest peat swamps.
The water in their natural habitat is soft and acidic and typically stained a brown colour because of the release of chemicals and tannins from decomposing organic matter. The substrate usually contains fallen leaves, branches and twigs and the habitats are often dimly lit due to the forest canopy above.
Unfortunately, these biotopes are endangered due to palm oil plantations, building developments and other human activities across the majority of Southeast Asia.
Other Rasboras of interest
What to feed the Emerald Eye Rasbora
Emerald Eye Rasboras are easy to feed. However, they will do much better on a varied diet. Therefore, it would be best to provide them with appropriately sized, high-quality dried food such as flakes and granules alongside regular offerings of frozen and freeze-dried food such as bloodworms, tubifex, brine shrimp and daphnia.
How to Sex the Emerald Eye Rasbora
It is somewhat challenging to distinguish between male and female Emerald Eye Rasboras. However, mature females are generally a little larger than males and are noticeably rounder-bellied. In addition, males can sometimes display a pinkish-red hue on their caudal fin during the breeding season, whilst females do not.
How to Breed the Emerald Eye Rasbora
Like numerous small Cyprinids, Emerald Eye Rasboras are an egg scattering, constant spawner that presents no parental care. However,
if your fish are in good condition, they will often spawn.
In a heavily planted, established aquarium, small numbers of fry may start to appear without intervention. However, if you would like to increase the yield of fry, a more controlled approach will be required.
You can condition the adult group together; however, you will need to set up a separate breeding tank. This tank should be dimly lit, and the bottom should be left bare or covered with some mesh with large enough holes for eggs to fall through but small enough holes so the adults cannot reach them. You can also use plastic grass matting, pebbles or marbles; these also work quite well.
The water itself should have a slightly acidic to neutral pH, and the temperature needs to be marginally higher than the general aquarium. You can add an internal power filter initially, and you should position this so that the flow is directed down the entire tank length.
Once the adult fish are well-conditioned and the females are noticeably full of eggs, you should then introduce one or two pairs to the breeding tank. You can encourage spawning by either adding small amounts of cooler water every few hours so that the tank is gradually topped and feeding them live and frozen foods several times throughout the day.
The adults will probably consume any eggs they find if given a chance, so it would be better if you removed them after a couple of days. At that point, you should take out the power filter and swap it for a sponge filter to avoid babies being sucked into it.
The incubation period is temperature-dependent; however, it usually takes between 18 and 48 hours for the eggs to hatch. The young will become free-swimming around 24 to 48 hours later.
You should initially provide your fry with Paramecium or infusoria, introducing baby brine shrimp and microworm once the fry is large enough to accept them.