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Maximum size : 4 cm

Emerald Dwarf Danio - Danio erythromicron : Complete Fish Profile & Care Guide

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The Emerald Dwarf Danio (Danio erythromicron) is a highly adaptable, peaceful, and durable species that makes a perfect addition to a community aquarium. With no specific demands regarding water chemistry, these fish can be housed with other popular species, including small Cyprinids, Tetras, Livebearers, Dwarf Cichlids, Catfish, and Loaches. As tight shoaling fish, Emerald Dwarf Danios tend to be somewhat timid and fare better in groups of at least ten individuals. Larger groups not only promote a more secure environment but also enhance their natural behavior as males compete for female attention, ultimately leading to an impressive display of vivid colors. In an aquarium setting, decor choices are not as crucial as water quality; however, these fish tend to thrive in a well-planted aquarium with a dark substrate. A natural-style set-up with a soft, sandy substrate and driftwood roots and branches forming plenty of shady areas can accentuate their natural beauty. The addition of dried leaf litter can also enhance the natural feel, offering more cover for the fish while promoting microbe colonies as decomposition occurs. These Danios prefer dim lighting, although it may hinder the use of some aquatic plants. Emerald Dwarf Danios exhibit a unique and captivating appearance, characterised by a light golden to pinkish body color contrasted by striking blue vertical stripes that extend throughout the entirety of their body, culminating in a blue patch that is surrounded by a white ring, reminiscent of an eye, just before the caudal fin. The fins of these fish are translucent, with a reddish-orange hue, particularly noticeable in the pelvic fins. Furthermore, male Emerald Dwarf Danios feature a distinctive red shading on their gill plates, adding to their visual appeal.\r\n

Emerald Dwarf Danio Photos

Sexual Dimorphism

Distinguishing between the male and female Emerald Dwarf Danios is a relatively uncomplicated process. The males exhibit more vibrant coloration and are marginally smaller in size than their female counterparts. Additionally, the male's fins possess a distinct reddish-orange tinge, while the female's fins are transparent and lack coloration. Further differentiation between the sexes can be observed in the rounder abdominal region of the females, which differs from the flatter abdomens typically seen in males.

Quick Facts

Scientific NameDanio erythromicron
Year Described1918
Other NamesEmerald Dwarf Rasbora, Thick Band Purple Zebra Danio, Cross-banded Dwarf Rasbora
Max Size4 cm
Aquarium LevelBottom - Middle
DifficultyBeginner - Intermediate
Best kept asGroups 10+
Lifespan3 - 5 years

Water Parameters

Water TypeFreshwater
PH7.2 - 8.2
KH2 - 10
TDS150 - 300
69 - 77
20.6 - 25

Natural Habitat

Emerald Dwarf Danios call the beautiful Lake Inle and its surrounding watersheds home. Nestled in the western Shan State of Myanmar Burma in Southeast Asia, this fish thrives in clear, shallow, neutral to slightly alkaline water with a lush, loamy substrate. Its habitat is a stunning haven of dense vegetation and submerged tree roots that create a harmonious ecosystem for the Emerald Dwarf Danio to flourish. Get ready to immerse yourself in the wondrous world of this exquisite species and discover the unique features that make it an extraordinary addition to the aquatic kingdom.


The breeding of Emerald Dwarf Danios can be facilitated seamlessly and continuously with proper aquarium water parameters. Although females tend to lay eggs frequently, it is highly recommended to establish a separate breeding tank as these fish tend to consume their eggs and fry. The breeding tank should contain multiple breeding mops or Java Moss to provide an ideal substrate for the deposition of eggs. To condition the fish for optimal breeding success, it is recommended to separate the males from the females and feed them a diet consisting of live foods for one to two weeks before spawning. A size of at least one inch and an overall healthy appearance is optimal for breeding. Once adequately conditioned, the females can be added to the breeding tank and the males added towards evening before the lights turn off. Typically, spawning will commence the following morning and persist for several days. Daily monitoring of the breeding mops or Java Moss is advised to remove any eggs and transfer them to a dedicated grow-out tank. In the grow-out tank, it is advisable to use an air stone to enhance water oxygenation without the use of a filter for the first couple of weeks. The transparent eggs typically hatch within 72 hours if maintained under favorable temperature conditions. The fry can be fed with infusoria, cyclops, paramecium or liquid fry food after they become free-swimming, which usually takes about a week. Commercial flake food, granules, or baby brine shrimp can serve as ideal food sources for the fry once they develop. Small daily water changes using water from the main aquarium should be carried out to maintain good water quality. After six to eight weeks, the babies can be gradually introduced into the main tank as they become larger than the parents' mouths.

Diet & feeding

Emerald Dwarf Danios exhibit a receptive nature towards live, frozen, or freeze-dried foods such as brine shrimp, mosquito larvae, daphnia, microworms, or bloodworm. Additionally, they eagerly accept micropellets, flake foods, and algae wafers, given they can accommodate their small mouths. Feeding these foods can significantly enhance the vibrant coloration of these fish, while also encouraging breeding behavior.\r\n

Frequently asked questions

The Emerald Dwarf Danio makes an excellent member of the community aquarium, providing you house them with smaller species of fish. These fish get on fine with similarly sized or smaller species and are ideal for the beginner aquarist. It would be best if you did not house Emerald Dwarf Danios with larger, very active or aggressive species.

Emerald Dwarf Danios originate from an isolated mountain lake of Inle and the surrounding waters in Shan State east of Myanmar. You can also find these fish near Loi Kaw in the neighbouring State of Kayah in Southeast Asia.

Emerald Dwarf Danios have blueish green bodies displaying iridescent turquoise stripes down their flanks. The anal and pelvic fins have a reddish-orange hue, and they usually have a black spot to the rear of the caudal peduncle. These fish also have pinkish gold colouring on their head through to the dorsal area.

Yes, in nature, Emerald Dwarf Danios are shoaling fish that swim together. It would be beneficial to your fish if you purchased at least 6, preferably more. You will find that your fish will fare much better and live longer in groups of their own kind.

Emerald Dwarf Danios will accept most foods in captivity. However, it would be better to provide your fish with good quality dried food such as pellets, flakes and granules as the staple and then give them live, frozen or freeze-dried foods once or twice a week. Also, it would help if you remember these fish are tiny; therefore, make sure the size of food is small enough for them to consume.

Emerald Dwarf Danios, when fully developed, can reach somewhere between 2.5 cm and 4 cm in length. So these fish are not very big, making them excellent fish for the nano aquarium.

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