Harlequin lancer catfish (Bagroides melapterus) care guide

Group
Freshwater fish
Family
Bagridae (bagrid catfishes)
Origin
South-east Asia: Thailand, Malaysia, Brunei and Indonesia.
Water
freshwater
Maximum size
34 cm
Temperature
23–28°C
pH
6–7.8
Hardness
3–18 dGH (estimated)
Minimum tank
600 litres
Temperament
peaceful_with_caution

Care

The harlequin lancer catfish is a slender bagrid catfish, silver with bold black spots and markings. FishBase and Wikipedia give a maximum of 34 cm total length (standard length will be somewhat less), so it is a large fish that needs a big tank as an adult. Detailed aquarium care figures were not available from the sources checked. A tank of about 600 litres for an adult is our estimate, based on its size and slim, active build. FishBase places it at a middle predatory level in the food chain, so expect it to eat small fish and invertebrates. It is listed as Least Concern on the IUCN Red List (FishBase, assessed 2018). We could not check the PlanetCatfish or Seriously Fish pages for this species, so this page is based on FishBase and Wikipedia only. Check the adult size and water needs with the seller before buying. Selling: our policies require the adult size and long-term tank needs to be stated clearly in the listing. Large fish must travel by a specialist live-animal courier (see the Livestock shipping guide). Sources: FishBase (fishbase.se/summary/Bagroides-melapterus.html); Wikipedia (en.wikipedia.org/wiki/Bagroidesmelapterus). Checked October 2026.

Diet

Omnivore: quality sinking pellets or wafers supplemented with frozen/live invertebrate foods and occasional vegetable matter.

Compatibility and tank mates

Likely to eat fish small enough to swallow. Keep with robust fish of a similar or larger size.

Last updated 5 October 2026. Community-edited care guide on Aquatic-Auctions.

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