News
SpeciesScientists Discover Mysterious New Fish in the Red Sea – and Have Never Seen It AgainOceanEye to eye with Britain's hidden sharks at SharkAdemy - OceanographicRiversIn October, biologists surveying a New York harbor for invasive fish pulled up a bright yellow one. It wasn't an invasive species at allOceanShedd Aquarium Sends Shark Eggs to Bolster Wild PopulationsSpeciesA rare fish has been found in Lake Ontario, North America, whose entire body is golden. It is a nati..OceanThe Great Sea Reef Is Fiji’s Wildest Dive, and a New Frontier for ConservationOceanEckerd College professor contributes to designating Biscayne Bay an Important Shark and Ray AreaSpeciesRio Verde Grande Survey Identifies Fifty-Three Fish Species Facing Flow ReductionsFisheriesAdams River Salmon Run in Thompson-NicolaIndiaHilsa production dropped 26% in five years, fisheries minister tells parliamentSpeciesScientists Discover Mysterious New Fish in the Red Sea – and Have Never Seen It AgainOceanEye to eye with Britain's hidden sharks at SharkAdemy - OceanographicRiversIn October, biologists surveying a New York harbor for invasive fish pulled up a bright yellow one. It wasn't an invasive species at allOceanShedd Aquarium Sends Shark Eggs to Bolster Wild PopulationsSpeciesA rare fish has been found in Lake Ontario, North America, whose entire body is golden. It is a nati..OceanThe Great Sea Reef Is Fiji’s Wildest Dive, and a New Frontier for ConservationOceanEckerd College professor contributes to designating Biscayne Bay an Important Shark and Ray AreaSpeciesRio Verde Grande Survey Identifies Fifty-Three Fish Species Facing Flow ReductionsFisheriesAdams River Salmon Run in Thompson-NicolaIndiaHilsa production dropped 26% in five years, fisheries minister tells parliament
EveryFish
A female blue perch ( Badis badis ).

Blue perch

Small Asian freshwater fish with blue fins

Photo: Kennyannydenny, CC BY-SA 3.0, via Wikimedia Commons

The blue perch is a tiny predatory fish from South Asia. It lives in slow waters like ponds and ditches across India and nearby nations. Males show bright blue colours during displays. Aquarists keep them for their compact size and distinct appearance.

Share on WhatsApp

  • Males develop blue fins and dark bands when excited
  • Found in Ganges, Brahmaputra, Mahanadi and Indus basins
  • Feeds on tiny invertebrates in ponds and ditches
  • Max length is around 8 cm
  • Previously grouped with Nandidae family

What it is

This small fish belongs to the family Badidae within the order Anabantiformes. It reaches a maximum length of about eight centimetres. The species shows clear differences between sexes. Males grow larger and develop vivid colours when excited. Their fins turn blue and dark vertical bands appear on their sides. Females remain smaller and display very little colour. This contrast helps distinguish the two genders in the wild or in tanks.

Where it lives

You can find this fish across northern India and eastern Pakistan. Its range extends into Bangladesh, Bhutan and Nepal. It inhabits major river basins including the Ganges, Brahmaputra, Mahanadi and Indus. The preferred habitats are calm and shallow waters. Look for them in ponds, slow moving rivers, drainage ditches and swampy areas. These environments provide the cover and prey density they need.

How it lives

It acts as a predator despite its small size. The diet consists mainly of tiny invertebrates found in the water. This feeding habit requires patience and stealth. The fish does not form large schools but may be solitary or in loose groups. Its behaviour changes during social interactions. Males become more active and colourful when competing or courting. This display signals readiness to other fish in the vicinity.

Blue perch
A drawing made by EveryFish from what this page says. It is a diagram, not a picture of the real fish.

Fish and people

Aquarium enthusiasts sometimes keep this species. Its compact size makes it suitable for smaller tanks. The striking blue colouration of adult males adds visual interest. Keepers appreciate the natural behaviours observed in captivity. It is not a major food fish in commercial markets. The primary human interaction is through the ornamental fish trade. Proper care requires mimicking its natural freshwater habitat conditions.

Questions people ask about Blue perch

How big does the blue perch get?

This fish stays quite small. The maximum total length recorded is around eight centimetres or three inches. This compact size makes it manageable for home aquariums.

Where does this fish live naturally?

It is native to South Asia. You will find it in northern India, eastern Pakistan, Bangladesh, Bhutan and Nepal. It prefers ponds, ditches and swamps in major river basins.

What do blue perch eat?

They are predatory fish that feed on tiny invertebrates. In the wild, they hunt small creatures found in their freshwater habitats. This diet supports their active lifestyle.

Good reading and sources

Where this page comes from

The facts on this page come from the Wikipedia article "Badis badis", written by its contributors and used under the CC BY-SA 4.0 licence, and from its Wikidata record (CC0). EveryFish rewrote the text in its own words, with AI assistance, and compares every page with the article to make sure no passage is copied. It may be reused under the same CC BY-SA 4.0 licence with a link back.

It may contain mistakes, and figures change over time. Nothing here is investment or buying advice. If something is wrong, tell us. Last refreshed 2026-11-15.

Like Blue perch

All perches, basses and snappers
🇺🇸 United States and 2 moreGreen sunfish A small, aggressive freshwater fish native to North America, known for its blue-green colour and invasive potential in nPerch-like · Rivers and lakes OceaniaBanded archerfish A silvery fish that spits water jets to catch prey.Perch-like · Estuaries and mangroves · 1767 Banded gourami 🇧🇩 Bangladesh and 4 moreBanded gourami Small tropical air-breathing fish with striped patternsPerch-like · Rivers and lakes · 1801 🇦🇺 AustraliaMurray cod Large Australian freshwater predator of the Murray-Darling basinPerch-like · Rivers and lakes · 1838

Photo credits on this page

The small pictures above come from Wikimedia Commons under free licences. Some are cropped to fit.

The weekly digest

Every Monday: the fish of the day, new pages on EveryFish, and the conferences and anniversaries of the week ahead.