Emerald Dwarf Rasbora: A Guide to Care and Keeping

Emerald Dwarf Rasboras are stunning freshwater fish that deserve more attention. Their vibrant colors and peaceful nature make them an excellent choice for home aquariums. Although underrated, they’re easy to care for and bring a lively charm to any tank.

Caring for your Emerald Dwarf Rasboras starts with understanding their preferences and needs. These tiny fish thrive in groups, so your aquarium should be prepared to house several of them. With proper care and a suitable environment, you’ll be delighted to watch them swim gracefully around their aquatic home.

In this article, we will cover everything you need to know about Emerald Dwarf Rasboras, from their size, ideal tank conditions, to their breeding habits and compatible tank mates. So, keep reading to make sure your little fish friends are happy and healthy in your care.

Species Profile

Emerald Dwarf Rasbora, a lovely addition to any freshwater aquarium, is known for its vibrant colors and active behavior. This small, shoaling fish thrives in well-decorated environments and gets along well with other peaceful tank mates.

Here is a quick glance at the Emerald Dwarf Rasbora’s properties:

Property Information
Scientific name Celestichthys erythromicron
Common names Emerald Dwarf Rasbora
Distribution Eastern Myanmar lakes
Size Up to 1 inch (2.5 cm)
Lifespan 3-5 years
Diet Omnivore
Temperament Peaceful, Schooling
Minimum tank size 10 gallons
Temperature 72-78°F (22-25°C)
pH 6.0-7.5
Water hardness 2-10 dGH
Care level Moderate
Filtration/Water Flow Moderate
Water type Freshwater
Breeding Egg-layers
Breeding difficulty Moderate
Compatibility Peaceful community aquariums

As an aquarist, you should provide the Emerald Dwarf Rasbora with a tank mimicking its natural habitat. This includes shallow water, dense vegetation, and a fertile soil substrate. They prefer to live in groups, so ensure you have at least six of these fish in your aquarium, ideally in a 20-gallon tank to allow for a larger group. Don’t forget about stable water conditions and a varied diet to keep these charming creatures healthy and happy.

Emerald Dwarf Rasbora Basics

Origins and Natural Habitat

Emerald Dwarf Rasboras (Celestichthys erythromicron) are freshwater fish native to Southeast Asia, specifically found in Myanmar. They thrive in slow-moving or stagnant waters, such as swamps and ponds, with plenty of submerged plants, which provide them with hiding spots and a source of food.

Size and Shape

These small, shoaling fish grow up to 1 inch (2.54 cm) in length and have a slender, elongated body. Their size makes them an ideal choice for smaller aquariums or as a peaceful addition to community tanks with other non-aggressive species.

Color and Markings

Emerald Dwarf Rasboras sport a stunning combination of colors, with a shimmering iridescent green body and red-orange stripes extending horizontally along their sides. Their fins are mostly translucent, adding an elegant touch to their appearance.


With proper care and a well-maintained aquarium, you can expect your Emerald Dwarf Rasboras to live for about 3 to 5 years. Ensuring their good health involves providing them with a suitable tank setup, including a steady water temperature of 72°F to 78°F (22°C to 25°C), a pH level between 7.2 and 7.9, and a total hardness of 150-300ppm. Additionally, feeding them a varied diet of high-quality dry foods and occasional live foods, such as brine shrimp and microworms, will keep them happy and healthy.

Diet and Feeding

Feeding your Emerald Dwarf Rasbora a well-balanced and varied diet is crucial to ensure their health and happiness. Offer them a mix of high-quality dry foods like micro pellets and flakes, as well as frozen or live foods like brine shrimp, daphnia, and bloodworms.

Remember, Emerald Dwarf Rasboras have small mouths, so make sure to provide food that is appropriately sized for them to consume easily. Feed them once or twice a day and give them only the amount of food they can consume within a few minutes.

Maintaining consistency in the feeding routine keeps your fish healthy and promotes their vibrant colors. However, be cautious not to overfeed, as excess food can lead to poor water quality and health issues for your fish. Overall, a nutritious and diverse diet will ensure your Emerald Dwarf Rasbora thrives in its environment.

Behavior and Temperament

Emerald Dwarf Rasboras are peaceful and friendly fish, making them an excellent choice for your aquarium. They are schooling fish, which means they thrive in a group of their own kind. Having a group of these fish in your tank creates a harmonious environment and a beautiful sight for you to enjoy.

When it comes to their temperaments, they are easygoing and get along well with other peaceful fish in a community setting. This makes them a fantastic option if you’re looking to diversify the species in your aquarium while maintaining a calm atmosphere.

It is essential, however, to provide your Emerald Dwarf Rasboras with a suitable environment. They prefer tanks with plenty of plants and hiding spots to feel secure and happy. Remember, a stress-free environment for these fish will promote their friendly nature and overall well-being.

So, if you’re looking for a beautiful, easy-going, and friendly fish to add to your aquarium, the Emerald Dwarf Rasbora is an excellent choice. Your tank will be full of life and color, providing enjoyment for you and a comfortable home for these delightful fish.

Care and Tank Requirements

Tank Size

Emerald Dwarf Rasboras are small fish, but it’s important to have an appropriately sized tank. For a group of 5-6 individuals, a minimum of 7.5 gallons is recommended. Keep in mind, the larger the tank, the more comfortable your fish will be.

Water Parameters

Emerald Dwarf Rasboras thrive in the following water parameters:

  • Water temperature: 72°F to 78°F
  • pH: 7.0 to 7.8

Keep a close eye on these parameters, and use an aquarium heater if necessary to maintain the ideal temperature.

Tank Setup and Decorations

A proper aquarium setup will ensure that your Emerald Dwarf Rasboras feel at home. They enjoy a densely planted tank, which provides hiding spots and mimics their natural habitat. Some recommended plants include:

  • Java moss
  • Anubias
  • Cryptocoryne

Using a fine sand or gravel substrate will also contribute to their well-being. Add some driftwood and rocks to provide additional hiding spaces and to create a natural look.

Filtration and Aeration

Emerald Dwarf Rasboras are sensitive to water quality changes, so having a good filtration system is essential. Choose a filter with a gentle flow rate to prevent stress on the fish. In addition, an air stone can be added to provide extra aeration and water movement.

Remember, consistent maintenance of your aquarium is essential in keeping your Emerald Dwarf Rasboras healthy and happy. Regular water changes and monitoring of water parameters will ensure a comfortable environment for your fish.

Suitable Tank Mates

When setting up a tank for your Emerald Dwarf Rasboras, you’ll want to consider their compatibility with other tank inhabitants. Since they are peaceful freshwater fish, they get along well with others of the same nature. Avoid introducing large or aggressive fish, as they might target your rasboras as prey and cause stress in the tank.

It is beneficial to choose tank mates similar in size, as they will harmonize well in the aquatic environment. Moreover, selecting fish from the same region as your rasboras, such as Lake Inle, can ensure a more comfortable living arrangement for all.

Here’s a list of suitable tank mates for your Emerald Dwarf Rasboras:

  • Sawbwa Barb
  • Celestial Pearl Danio
  • Glowlight Danio
  • Red Dwarf Rasbora
  • Small types of catfish
  • Dario Hysginon
  • Cherry Shrimp
  • Most freshwater snails

By carefully selecting the right companions for your rasboras, you can create a diverse and peaceful community aquarium that’s enjoyable for you and your fish.

Breeding Process

To breed Emerald Dwarf Rasboras, start by setting up a separate breeding tank with well-cycled water. Add spawning mops or leafy plants to the tank, as these will provide ideal locations for egg-laying.

Next, introduce a bonded pair or a group of two males and multiple females into the breeding tank. Keep in mind that having more fish may increase the risk of eggs being consumed, so monitor their behavior closely. Feed your breeding group high-protein foods to encourage spawning.

Once females start laying eggs, you’ll notice about 30 eggs throughout the tank. These eggs have a mild adhesive nature, so they might stick to leaves or decor. Be patient, as the eggs will hatch after about 72 hours.

When the fry hatch, they will survive on their egg sac for an additional three to four days before becoming free-swimming. During this time, it’s essential to offer infusoria or powdered fish food until the fry are ready for baby brine shrimp.

By following these steps, you’ll maximize the survival rates of your beautiful Emerald Dwarf Rasbora offspring and enjoy the rewarding process of breeding these colorful, lively fish.

Common Diseases and Treatments

Ich: Ich, or White Spot Disease, is a common ailment in Emerald Dwarf Rasboras. Keep an eye out for white spots on their bodies and fins. To treat it, gradually raise the tank temperature to 82°F and use over-the-counter anti-ich medications.

Fin Rot: Fin rot is caused by bacterial infections, which can lead to frayed or discolored fins. Maintain good water quality and add a fin rot treatment to your aquarium to curb its progression.

Fungal Infections: These can manifest as white, cotton-like growths on your fish. Fungal treatments can be found at most pet stores and are effective in clearing up the infection.

Remember, prevention is key to maintaining the health of your Emerald Dwarf Rasboras. Frequent water changes, proper filtration, and avoiding overcrowding can help minimize the risk of diseases. If you notice any abnormal behaviors or symptoms, act quickly to identify and address the issue.

Frequently Asked Questions

What do Emerald Dwarf Rasboras eat?

Emerald Dwarf Rasboras are omnivores and enjoy a varied diet. You can feed them high-quality flakes or micro pellets, as well as frozen or live foods, such as daphnia, brine shrimp, or bloodworms. By providing a diverse diet, you’ll ensure they receive the necessary nutrients for optimum health.

How big do they grow?

Emerald Dwarf Rasboras are small fish, reaching a maximum size of 1 inch (2.54 cm). Their small size makes them suitable for smaller aquariums, but keep in mind that they are a shoaling fish and thrive in groups.

Are they suitable for beginner aquarists?

Yes, Emerald Dwarf Rasboras are a great choice for beginner aquarists because they are peaceful, easy to care for, and quite hardy. Additionally, their vibrant colors and active nature make them a visually appealing addition to your aquarium.

What is their ideal water temperature?

The ideal water temperature for Emerald Dwarf Rasboras is between 72° – 79° F (22° – 26° C). Maintaining a stable temperature within this range is important to keep these fish healthy and stress-free.

What tank mates are compatible?

Due to their peaceful nature, Emerald Dwarf Rasboras can be kept with a variety of tank mates. They thrive in community tanks with other small, peaceful fish, such as tetras, small barbs, and other rasboras. Invertebrates, such as snails and dwarf shrimp, can also be suitable tank mates. However, it’s best to avoid larger or aggressive fish that may see the rasboras as prey or stress them out.