The Sundasalanx fish, known scientifically as Sundasalanx microps, belongs to the family Clupeidae. This fish is exotic for several reasons: it is rarely found in aquariums, and its appearance is unusual. Keeping these fish involves various difficulties, especially regarding their adaptation, as they are caught from their natural environment. They do not breed in aquarium conditions. They can only be recommended to experienced aquarists.
- Required aquarium volume
- 40 L
- Size in aquarium
- 1.5 – 2 cm
- Temperature
- 25 – 28 °C
- Temperament
- Peaceful (regular)
Description
This fish is strikingly miniature, even tiny. Adults grow to only 2 cm in length. Sexual dimorphism is weakly expressed, and it is almost impossible to distinguish males from females externally. Sundasalanx has an elongated body and a very small head. Its main distinguishing feature is not so much its coloration as its absence, as the fish is almost completely transparent. Through the body, the skeleton and internal organs are clearly visible, gathered in a small, silvery “sac.”
Habitat
Its natural habitat is in Southeast Asia, south of the Kra Isthmus, which connects the Malay Peninsula to the Asian continent, in the modern territories of Thailand and Malaysia. These fish prefer murky waters with slow currents or stagnant water. During the day, they usually stay near the silty bottom, and at night and dusk, they may rise closer to the surface.
Behavior and Compatibility
These peaceful schooling fish, however, due to their tiny size, have a very limited choice of aquarium mates. It is advisable to keep them separately from other fish species.
Care and Maintenance
Thanks to their modest size, adult Sundasalanx fish can feel comfortable in nano-aquariums of about 20 liters. When decorating such an aquarium, it is recommended to use a soft sandy substrate, driftwood, and low-growing aquatic plants that can thrive in low light. It is important to provide an efficient filtration system to maintain high water quality, and to regularly clean the aquarium. When choosing a filter, opt for models that do not create excessive current and whose water intake openings are reliably protected to prevent accidental suction of the fish into the cleaning system. Weekly partial water changes (20–30% of the total volume) are also an essential procedure to prevent the accumulation of organic waste.
Diet
In natural conditions, the diet of these fish consists mainly of microorganisms such as invertebrates, crustaceans, and annelids. In a home aquarium, they should be offered similar products, for example, Artemia nauplii or Daphnia. It is also possible that they will accept specialized foods developed for fry.
Breeding and Reproduction
Based on available sources, a separate block cannot be compiled: the data is insufficient or contradictory. The entry can be updated later when verified information becomes available.
Diseases
Based on available sources, a separate block cannot be compiled: the data is insufficient or contradictory. The entry can be updated later when verified information becomes available.
How to choose
This species is extremely rare in retail and is practically not represented in the aquarium trade. When purchasing, it should be noted that the fish are very sensitive to transportation and keeping conditions, so it is extremely important to assess their general condition in the store. Healthy individuals should be active, exhibit schooling behavior, and show no visible damage or signs of emaciation. Due to their small size and specific dietary requirements, it is recommended to check with the seller in advance what the fish are fed and how they have been adapted to captivity.
Frequently asked questions
The essentials: size, tank volume, water parameters and care
How big does Sundasalanx get?
An adult reaches 1.5–2 cm in length. Plan the tank around the maximum size: the fish quickly outgrows a cramped setup.
What size aquarium does Sundasalanx need?
The minimum recommended volume is 40 L. A smaller tank speeds up nitrate build-up and raises stress levels.
What water parameters does Sundasalanx need?
Temperature 25–28 °C, pH 6–8, hardness 3–12 dGH. Stability matters more than exact values: sudden swings are harder on the fish than a small deviation from the ideal.
How long does Sundasalanx live?
Around 1 years when kept properly. Lifespan depends directly on tank volume, water quality and a varied diet.
Is Sundasalanx aggressive?
Temperament: peaceful (regular). Keep this in mind when choosing tank mates.
How many Sundasalanx should be kept together?
Recommended setup: schooling (usually from 5–6 individuals and more). Ignoring this is a common cause of stress and disease.
What does Sundasalanx eat?
Diet type: small / appropriate size / pieces. Feed small portions that are finished within a couple of minutes — overfeeding does more harm than underfeeding.
What is the scientific name of Sundasalanx?
The scientific name of the species is Sundasalanx microps, family Herrings (Clupeidae).
