Epiplatys annulatus
Tiny surface-dwelling killifish, black-and-cream barred body with a fan-shaped tail that glows orange in males. Strict surface dweller; needs dense floating plants and dim tannin-stained blackwater. Breed continuously among Java moss.
Clown Killifish (Epiplatys annulatus) reaches 3–3.5 cm as an adult and needs a minimum tank of 30 L. Native to Coastal Sierra Leone, Guinea, Liberia, it lives in the top water column with a peaceful temperament. Aim for 22–26 °C, pH 4.5–6.5, and 1–6 dGH hardness. Lifespan is 3–4 years with good care. Keep clown killifish in groups of 4+, loose group schoolers need numbers to display natural behaviour. Diet: micropredator, Microworms, baby brine shrimp, fruit flies, powder fry food. Will not pick from the substrate, feed at the surface. Plant-safe: Yes. Shrimp-safe: Yes (adults only, will hunt shrimplets).
Care at a glance
Tiny surface-dwelling killifish, black-and-cream barred body with a fan-shaped tail that glows orange in males. Strict surface dweller; needs dense floating plants and dim tannin-stained blackwater. Breed continuously among Java moss.
By Mike ElmiraUpdated 2 min read
Part of our complete guide to aquarium fish for the planted tank.
The parameters that decide whether clown killifish fits in your tank.
Top
No
Small group of 4+
Nothobranchiidae
Micropredator
Microworms, baby brine shrimp, fruit flies, powder fry food. Will not pick from the substrate, feed at the surface.
3–4 yrs
Easy
Small forest pools and rivulets of West Africa
Coastal Sierra Leone, Guinea, Liberia
Tank-mate safety and the species this one is documented to thrive (or fail) alongside.
Best species-only. With caution: cherry shrimp adults (will hunt shrimplets), sparkling gouramis, ember tetras.
Anything that occupies the upper water column (they'll be stressed). Larger fish (they're tiny). Fast feeders that outcompete them.
Hard-won lessons from the tank.
Set up a dedicated 30 L blackwater nano with RO + tannins + dense moss carpet + floating plants — this is essentially their dream habitat. Drop fruit flies or mosquito larvae at the surface and watch them attack from below. A breeding colony self-sustains in a properly-set tank, becoming a true ecosystem rather than a stocking decision.
Genus 'Epiplatys' = 'flat above' (referring to the dorsal head shape). Species 'annulatus' = 'ringed' for the body bands.
What can go wrong and how to spot it.
Failure modes, in order of how dramatic the fix is.
Sensitive to alkaline water and parameter swings. Most issues in trade come from being sold in too-hard tap water.
Often sold as 'easy nano fish' — they're easy ONLY in proper soft-water blackwater setup. Standard community-tank conditions kill them within months.
The practical routine, read top to bottom.
30 L+ nano blackwater. RO water + tannins required for long-term health. Heavily planted with surface plants (frogbit, dwarf water lettuce) and Java moss throughout. Catappa leaves and alder cones. Sponge filter only — they cannot handle current. TIGHT LID — they jump.
3 weeks in a soft-water QT with tannins.
Where it comes from, how it behaves, and the variants you'll see at retail.
Where it lived before it came home.
Coastal blackwater swamps and slow streams of Sierra Leone, Guinea, and Liberia. Very soft (~1 dGH), extremely acidic (pH 4.5–6.0) tannin-stained water with dense surface vegetation and leaf litter.
Surface insects, mosquito larvae, ant falls, micro-crustaceans.
Habitat in West Africa is reduced by deforestation and agricultural runoff. Captive breeding is common in hobbyist circles.
How they pair, reproduce, and grow.
Males have an orange-yellow body with intense black bands, plus a fan-shaped tail with orange center and black-and-white edges. Females are paler with simpler tail patterns and rounder bodies.
Continuous spawners. Eggs deposited among Java moss or spawning mops. Soft acidic water, dim lighting, tannins. Fry hatch in 10–14 days and are tiny — need infusoria initially. In a planted blackwater colony tank, fry survive among the moss without intervention.
The named cultivars and the lookalikes worth flagging.
Wild type, occasionally 'super red' lines from selective breeding.
Direct answers to the questions search engines and AI assistants surface most often about this species.
Clown Killifish (Epiplatys annulatus) needs a minimum tank of 30 L. They live in the top water column and should be kept in groups of 4+, so a longer footprint matters more than depth.
Target 22–26 °C, pH 4.5–6.5, and 1–6 dGH hardness. Acclimate slowly when moving them between water sources.
Shrimp safety: Yes (adults only, will hunt shrimplets). Plant safety: Yes.
Clown Killifish are micropredator. Microworms, baby brine shrimp, fruit flies, powder fry food. Will not pick from the substrate, feed at the surface.
On Fin & Stem's 1–5 difficulty scale this species rates 3/5. Intermediate, stable parameters and a mature tank matter. Breeding difficulty: easy.
Typical lifespan in a well-maintained tank is 3–4 years.
A planted tank is a system. Pair this fish with one entry from each other pillar to plan the whole scape.
