An overview of the wonderful Epiplatys annulatus. Discover where they come from and how to keep them.
Nano aquariums are increasingly popular because they can be squeezed into small spaces in the home. Plus, in the world of aquascaping and aquarium plants, nano tanks are cheaper too. The equipment is often cheaper to buy, they have lower running costs and you need less hardscape and live plants to fill them. But, the question of what fish to stock often follows soon after.
Related article: Top 10 small fish for nano aquariums.
That brings us nicely onto the subject of this article, the clown killifish (Epiplatys annulatus). You may know them as the rocket panchax, a name that refers to the attractive tail of the males, or the banded panchax. These stunning nano fish reach just 3cm (1.2") in length meaning they're an ideal option for small aquariums.
These fish aren't too expensive to buy, enjoy the cover provided by a densely planted aquarium and are peaceful.
In this clown killifish care guide, we’ll cover tank size, water parameters, feeding, tank mates and breeding Epiplatys annulatus. Giving you the information so that you can decide whether this beautiful West African killifish is right for your planted tank.
Clown killifish - Photo by Alex Bell
Natural habitat of Epiplatys annulatus
This wonderful small fish lives in West Africa, occurring in Sierra Leone, Guinea and Liberia. They dwell in coastal swamps, forest streams and other areas of shallow water. A common feature across all these habitats is slow moving, sometimes even completely still, water.
Jelly bean tetra live alongside clown killifish - Photo by Alex Bell
In areas where the waters are not under a closed canopy, aquatic plants, including Nymphaea, are abundant. In sheltered areas, these tiny fish use marginal plants for cover. They occur alongside Norman's lampeyes (Poropanchax normani), jelly bean tetra (Ladigesia roloffi), adonis tetra (Lepidarchus adonis), African butterfly cichlid (Anomalochromis thomasi) and many other species sometimes available in the hobby.
A great video showing the type of habitat they live in is available on YouTube by Russell Tate.
Clown killifish tank size and setup
A tank of about 45cm (18") long will be perfect for a group of these tropical fish. Any smaller and you won't be able to keep enough of them to help them settle.
Filtration should be gentle but efficient. A mature air driven sponge filter would suffice, as would a small hang-on the back or internal. The important thing is that it is mature before adding the fish. Also, check the intake size of your filter, these are small fish and can find their way into filters if the intake is too large.
Air driven sponge filter - Photo by Shutterstock
Being tropical fish, you will need a heater, set to 20-25°C (68-77°F). Perhaps the most critical thing is you should have some sort of lid or cover glass. These fish are excellent jumpers, and an open top aquarium filled to the top with water is a death sentence. Although, you can sometimes resuscitate escaped fish.
Rimless aquariums only work if they are only partially filled. This will also allow you to grow attractive emergent plants which can help provide shade for the fish.
Lighting does not need to be too strong, clown killis do best under fairly dim conditions. If using a powerful LED light, add floating plants to help provide some shade while the other plants grow in.
Aquascaping a fish tank for rocket panchax
The fish you encounter in aquatic stores will likely be captive bred. This means a true biotope is not a necessity, although it can work great.
A sandy substrate replicates their habitat well, but aquarium soils are also suitable. A dark substrate can enhance the colours of the fish. Decorate with aquarium safe woods, opt for branchy and root like pieces for an authentic look. They will provide clear boundaries, allowing the males to occupy small territories in an attempt to woo a mate.
You can use rocks and stones, just ensure they are inert as calcium carbonate rich stones would not be suitable. They will raise the water hardness and pH, which the killifish will not appreciate. A handful of botanicals in the foreground will complete the natural look. Equally, an open sandy area with some small plants, like Cryptocoryne parva, would look great in a low tech planted aquascape.
Clown killis will appreciate dense plant growth - Photo by Alex Bell
Fill the aquarium with plenty of plants to suit your set up. Nymphaea, Anubias, Bolbitis, Crinum all originate in Africa and could create a loose African biotope feel. Alternatively, Java fern, Bucephalandra, Cryptocoryne, Eleocharis, and Echinodorus can all thrive in lower lighting and would make good choices.
Clown killifish care
As we already touched on, these fish are truly tropical, rather than temperate. So aim for 20-25°C (68-77°F) for your aquarium's water temperature. They also need soft and acidic water to thrive. A pH of 7 is the upper limit and you want to aim for below 8° hardness.
Feeding is generally easy, accepting most common aquarium foods. Frozen or live foods, like baby brine shrimp, will get them into top condition, while fish flakes and micro granules are a good staple.
Female clown killifish lack the bright tail of the males - Photo by Shutterstock
In small tanks, things go south quickly, and these fish are sensitive to poor water quality. Regular water changes are a must, and ensure you have a good test kit to hand. Only buy this fish if you can provide the care that they require – they are not a good beginner fish.
Any tank mates must be equally small and peaceful, otherwise they will outcompete the killifish. Small characins, rasboras like Boraras, dwarf corydoras, and kuhli loaches all make great options and will enjoy similar conditions.
Breeding Epiplatys annulatus
Like with many fish, mature clown killifish will often spawn when provided with the correct care. However, any tank mates will likely eat the eggs and tiny fry in a community setting. Therefore a dedicated breeding tank is the best option if this is your aim.
They will lay their eggs in Java moss, the roots of floating plants or spawning mops. Fry typically hatch after around 10 days when kept at the upper end of their temperature range. The small fry need equally small foods, a mature aquarium with botanicals and live plants will likely have some microorganisms for the fry to feed on. Culture infusoria or rotifers in more sterile conditions, or to supplement the natural foods.
You can successfully rear fry alongside the adults. However, separating each batch of fry is the best way to maximise numbers.
Spawning mops can work for breeding clown killifish - Photo by Shutterstock
Clown killifish Fact File
Scientific name: Epiplatys annulatus
Size: Males up to 3cm (1.2”), females typically stay smaller.
Origin: Sierra Leone, Guinea and Liberia.
Habitat: Swamps and sluggish streams and rivers.
Tank size: 45x30x20cm (18x12x8”).
Water requirements: Soft and acidic water with a pH below 7 and a hardness below 8°H.
Temperature: 20-25°C (68-77°F)
Temperament: A social species that will be shy if not kept in a group. Aim for at least 8 individuals to see them at their best. They can be suitable for a carefully planned small community.
Feeding: Naturally feeds on small invertebrates. Replicate this by feeding insect based prepared foods along with frozen and live foods such as Daphnia, Cyclops and brine shrimp.
Availability & cost: One of the more commonly seen killifish in aquatic stores. Expect to pay around £4 each.