A surface fish of 35 mm, and four names it no longer has
A clown killifish is a inch and a half of West African surface fish, kept in tanks smaller than most records here will allow. It is published for water down to pH 4.0, which only our kuhli loach record goes below, and two of our four sources refuse to publish how long it lives.
Wikipedia gives the current name, Epiplatys annulatus, Boulenger, 1915, and four it has carried before: Haplochilus annulatus, Aplocheilus annulatus, Panchax annulatus and Pseudepiplatys annulatus. Seriously Fish adds that the genus Pseudepiplatys is now considered invalid.
The common names travel too. Seriously Fish gives rocket killifish and banded panchax; Wikipedia gives clown killi and banded panchax; Aquarium Co-Op uses both clown killifish and rocket killifish on the same page. Five scientific names and four common ones for one 35 mm fish, which is worth knowing when comparing two care sheets that appear to be about different animals.
On range the two agree: West African coastal lowlands in Guinea, Sierra Leone and Liberia, with Wikipedia giving the type locality as Maka near the Moa River in Sierra Leone and listing the species as Least Concern.
One note about the sources rather than the fish. The Wikipedia article is flagged as a stub, and it publishes no size, no water figures, no lifespan and nothing about the trade. On most records here it is one of the two most useful sources; on this one it is the name and the range and nothing else.
Why this record was written now
- The gap
- Five thousand five hundred searches a month, and the keyword map notes that Google answers it with an AI overview every time.
- What it changes
- It is the second surface record here after the betta, the lowest pH floor on the site at 4.0, and the ninth record at five gallons or under.
- What it does not
- One blank, the growth rate. And no lifespan from either of the two sources this site usually leans on.
The water, and the lowest pH floor on this site
| Source | Temperature | pH | Hardness | Tank and group |
|---|---|---|---|---|
| Seriously Fish | 68 to 79 °F | 4.0 to 7.0 | 1 to 8 dGH | A base of 45 by 30 cm, and at least 8 to 10 fish |
| Aquarium Co-Op | 67 to 80 °F | not stated | not stated | A 5-gallon nano tank or larger, 1 male to 2 or 3 females |
| Shrimpy Business | 67 to 80 °F | 4.0 to 7.0 | 4 to 8 dKH | 5 gal minimum, 10 preferable, groups of 8 to 10 |
| Wikipedia | not stated | not stated | not stated | not stated |
The two sources that publish a pH publish the same one, 4.0 to 7.0, and only one record here goes lower. Our kuhli loach record carries 3.5 to 7.0, our ember tetra record 5.5 to 7.0, and our chili rasbora record 6.0 to 7.0 with a source recording wild black water as low as pH 4.0. Everything else here starts at 6.0 or above, so this fish and the kuhli loach are the two records written for water most keepers never make.
The ceiling is the half most keepers will hit first. Seven point zero means this fish tops out at neutral, and three records here start there: our platy record at 7.0 to 8.0, our ramshorn snail record at 7.0 to 7.5 and our assassin snail record at 7.0 to 7.5. A tank that suits any of those three is at the edge of what this fish is published for.
On temperature the three bands share 68 to 79 °F, and the useful part is the floor. This is one of very few fish here that does not need a heater in a warm room: only our goldfish record at 68 to 74 sits as low, and our platy record starts at 70.
On hardness only Seriously Fish publishes general hardness, 1 to 8 dGH, which is 18 to 143 ppm. Shrimpy Business publishes 4 to 8 dKH, which is carbonate hardness and a different measurement. Both point at soft water, and read against our platy record at 214 to 321 ppm these two fish are at opposite ends of the same hobby.
Clown killifish tank size, and the group that does not fit in it
Two figures on this record are published by different sources for different arrangements, and multiplying them is where the problem appears.
- Aquarium Co-Op: a 5-gallon nano tank or larger, and separately, 1 male for every 2 to 3 females.
- Shrimpy Business: a minimum tank size of 5 gallons is recommended, though 10 gallons or larger is preferable, and they prefer to be kept in groups of 8 to 10 individuals.
- Seriously Fish: no volume at all, minimum base dimensions of 45 by 30 cm, 18 by 12 in, or equivalent, and buy at least 8 to 10 specimens since this species is relatively gregarious. Smaller aquaria can be used for breeding purposes.
So the group is eight to ten fish on two sources and three or four on the ratio the third publishes. A keeper following Aquarium Co-Op’s ratio alone ends up with a third of the group the other two ask for, and a keeper following the group figure in a five gallon has ten fish in the smallest tank any source allows.
The 45 by 30 cm base is the figure that reconciles them, and it is about eleven gallons. That is the footprint Seriously Fish asks for and it is roughly twice what the two care sources will accept, which is the same shape our chili rasbora record found: a nano fish sold for a nano tank, with the specialist source asking for a bigger box than the retailers.
This is the ninth record on this site at five gallons or under, and our stocking page lists all of them. Our stocking calculator works from the five gallon figure and the group of ten is what makes it tight.
The lid, which one source is specific about
Aquarium Co-Op: they will not jump out if you keep a tight lid or hood with all of the gaps covered. That is the only jumping warning on this record and the only one on this site phrased as a condition rather than a risk, and it follows from the layer: a surface fish is a fish already at the top of the water.
The full record
| Field | Recorded | Where it comes from |
|---|---|---|
| Minimum tank | 5 gal | Three sources and two answers. Aquarium Co-Op: a 5-gallon nano tank or larger. Shrimpy Business: a minimum tank size of 5 gallons is recommended, though 10 gallons or larger is preferable. Seriously Fish gives no volume and asks for minimum base dimensions of 45 by 30 cm, 18 by 12 in, or equivalent, adding that smaller aquaria can be used for breeding purposes. That footprint is roughly eleven gallons, so the specialist source asks for about twice what the two care sources will accept. The row prints 5 gallons because two of three publish it, and station 03 prints the group figure that complicates it: Seriously Fish asks for 8 to 10 fish in that 45 by 30 cm base. |
| Temperature | 68 to 79 °F | Three bands and they nearly agree. Aquarium Co-Op: 67 to 80 °F, 19 to 26 C. Shrimpy Business: adaptable to water temperatures between 67 °F and 80 °F. Seriously Fish: 20 to 26 C, 68 to 79 °F. The row prints the span all three contain. This is one of the few fish on this site that a warm room could hold without a heater. Only two fish records start as low or lower: our guppy record at 63 to 82 and our goldfish record at 68 to 74. Our platy record starts at 70 and everything else here starts at 72 or above. |
| pH | 4.0 to 7.0 | Two sources publish a band and they publish the same one. Seriously Fish: 4.0 to 7.0. Shrimpy Business: pH ranging from 4.0 to 7.0. Aquarium Co-Op publishes no pH at all. That floor of 4.0 is the second lowest on this site, after our kuhli loach record at 3.5, and it is a point and a half below everything else: our ember tetra record carries 5.5 to 7.0, our chili rasbora record carries 6.0 to 7.0 with a source recording black water at a pH as low as 4.0 in the wild, and every other record here starts at 6.0 or above. The ceiling matters as much as the floor: 7.0 means this fish tops out at neutral, which is where three records here start. |
| Hardness | 18 to 143 ppm | One source publishes general hardness and one publishes carbonate hardness. Seriously Fish: 1 to 8 dGH, which is 18 to 143 ppm, and the row prints it because it is the only dGH figure on the record. Shrimpy Business publishes 4 to 8 dKH, which measures carbonate hardness rather than general hardness, the same mismatch our clown loach, assassin snail and ramshorn snail records ran into. Aquarium Co-Op publishes nothing. Soft water is the direction all of it points, and read against our platy record at 214 to 321 ppm this fish sits at the other end of the hobby. |
| Adult size | 1.4 in (35 mm) | Three sources and one figure, which happens on almost no record here. Aquarium Co-Op: up to 1.4 inches, 3.5 cm. Shrimpy Business: up to 1.4 inches. Seriously Fish: 35 mm SL, 1.4 in SL, which is standard length and therefore measured to the tail base rather than the tail tip. Wikipedia publishes no size. It makes this the fifth smallest fish on this site, behind the ember tetra, the chili rasbora and the male of our least killifish record at 20 mm, and the pea puffer at one inch. |
| Diet | Micro predator. It takes dried food and wants live | All three care sources describe the same animal and none of them is happy with a dry-only diet. Seriously Fish: this species accepts dried foods but should receive daily meals of small live and frozen fare such as Artemia nauplii, Daphnia, Moina and grindal worm. Shrimpy Business calls them micro predators and says they may accept a variety of dried foods, but they will most appreciate live and frozen foods, naming daphnia, artemia, brine shrimp and micro worms. Aquarium Co-Op is the most permissive and the most specific about the shape of the food rather than its origin: tiny floating foods such as fry food, crushed flakes and freeze-dried daphnia, plus slow-sinking foods including live baby brine shrimp, frozen cyclops and nano pellets. Two of the three say dried food is accepted and not sufficient, and all three build the diet around something small enough for a mouth on a 35 mm fish. |
| Water column | Surface | Aquarium Co-Op describes it in the title of its own guide, a top-dwelling nano fish, and Shrimpy Business asks for tank mates among small top-to-middle dwelling species. Seriously Fish asks for a well-planted tank with floating plants, which is the same layer read from the plants rather than the fish. This is the second surface record on this site after our betta record, and the two share the requirement that follows from it: the food has to reach the top of the water, which is why Aquarium Co-Op leads with tiny floating foods. |
| Lifespan | 2 to 5 years | Two sources and a factor of two between them. Aquarium Co-Op: about 2 to 3 years long. Shrimpy Business: up to 5 years. Seriously Fish and Wikipedia publish no lifespan at all. Station 04 prints the pair as the dispute on this record, because on a fish this size the difference between two years and five is the difference between a season and a commitment, and neither source explains the gap. |
| Growth rate | Not recorded yet | No source publishes a rate, a size at an age or a maturity date. The only timescale on the record is the incubation period in station 08, and for once our sources agree on it. |
The same nine fields for every animal on this site are in the A to Z index.
Where our sources disagree
Every record here names a disagreement. On this one it is the figure a buyer is committing to.
Aquarium Co-Op
Clown killifish live about 2-3 years long.
Shrimpy Business
Lifespan: up to 5 years.
What we record: we print both and take neither, and the two most technical sources on this record decline to publish a lifespan at all. Seriously Fish gives none and the Wikipedia article, which is flagged as a stub, gives none either.
So the only two figures available differ by a factor of two and neither is qualified. The row carries 2 to 5 years because that is the span the two cover. What is worth noting is which source says which: the retailer that sells the fish gives the shorter figure and the shrimp specialist gives the longer one, which is the opposite of the direction a reader might expect.
Our guppy record is the only place on this site where a lifespan has a mechanism attached to it, and nothing like that exists here.
Not an ideal community fish, and six species one source names anyway
The two positions
Seriously Fish is direct: in its own spelling, peaceful with other species but does not make an ideal community fish due to its small size and somewhat specialised requirements
, and it recommends small tetras and similarly-sized quiet species.
Aquarium Co-Op publishes a list instead: celestial pearl danios, Norman lampeye killifish, chili rasboras, pygmy cory catfish, snails, and other nano species, with the betta added as a case that depends on individual temperament.
Shrimpy Business calls it a peaceful predator and asks for small top-to-middle dwelling species plus peaceful bottom dwellers like corydoras catfish, avoiding aggressive and carnivorous species.
The disagreement is not about temperament and all three sources say so. It is about the water and the size, which is exactly what station 02 shows: a pH ceiling of 7.0 and a hardness ceiling of 143 ppm rule out more of this site than any temperament would.
Against our own records
Two of the six species Aquarium Co-Op names are written here, and both work on water as well as temperament. Our chili rasbora record carries pH 6.0 to 7.0 and 54 to 179 ppm, so it meets this record from 6.0 to 7.0 and from 54 to 143. Our corydoras record covers the pygmy species by name and meets it from 6.5 to 7.0 and from 18 to 143.
The third recommendation is the one our own rows refuse. Aquarium Co-Op names snails, and our nerite snail record carries pH 7.5 to 8.5, which does not meet 4.0 to 7.0 anywhere. A snail shell needs carbonate and this fish is published for water with almost none, so the pairing is a caution on our tank mates grid with the two pH rows printed.
The fourth of the six is written now, and it arrives as a condition rather than a gap. Our celestial pearl danio record carries pH 6.6 to 7.5, so it meets this record between 6.6 and 7.0 and nowhere else, which is four tenths of a point to hit. On temperature the two are comfortable, 73 to 76 sitting inside 68 to 79. Only the Norman lampeye killifish is still unwritten. So of six named tank mates this site can speak to four, and two of the four are pairings our own rows argue with rather than endorse.
Clown killifish with shrimp: the most precise answer on this site
Most records here answer the shrimp question with a rule or a hedge. This one has a sentence that splits it exactly.
Aquarium Co-Op: clown killifish do not seem to eat adult dwarf shrimp, but baby shrimp are fair game.
Shrimpy Business, which is a shrimp specialist and the source our cherry shrimp record cites, does not address it at all. Seriously Fish does not raise shrimp. So the answer rests on one source, and that source is the only one on this site to put the line between an adult and a juvenile of the same animal.
What that means in a real tank
Our cherry shrimp record carries a 30 to 40 mm adult whose young hatch at about a millimeter. Both halves of Aquarium Co-Op’s sentence therefore apply to the same tank at the same time: the colony persists and each generation is thinned. Our grid marks the pairing a caution rather than a refusal because that is precisely what our source describes.
Read it beside the other shrimp answers this site holds and the range of precision is the point:
- Our assassin snail record: three sources say yes with three different conditions, only the weak, the sick or the molting, or shrimp fry, or smaller shrimp.
- Our apistogramma guide: all three care sources say yes with no condition at all.
- Our betta record: bettas are notorious for going after shrimp, and our grid refuses it outright.
- Our clown loach record: not one of five sources mentions shrimp, and the record says so.
Five records, five different levels of certainty about the same question, and this is the only one where a source draws the line at the age of the shrimp rather than at the species.
Clown killifish male vs female, and the tail that tells you
Three sources answer and for once they are describing the same feature.
- Aquarium Co-Op: male rocket killifish have brightly colored tails, whereas females have a clear tail.
- Seriously Fish, in its own spelling:
Males are more colourful, develop more-extended fins and grow larger than females.
- Shrimpy Business: males tend to develop more intense coloration and longer fins than females.
The tail is the useful one because it is a presence or an absence rather than a comparison: a colored tail against a clear tail can be read on a single fish, while more colorful and longer finned needs two fish side by side.
That matters more here than on most records, because Aquarium Co-Op asks for one male to every two or three females, so a buyer has to sex the fish in the shop tank rather than at home. Our apistogramma guide carries the opposite situation, where subdominant males hide their colors and look like females, and our honey gourami record carries a color change that does not happen at all in the strains shops sell.
Nothing our sources publish gives a size difference in figures, and the group figure of 8 to 10 makes the ratio question harder rather than easier: ten fish at one male to three females is not a ratio that divides evenly.
Clown killifish breeding, and the one figure everyone agrees on
The eggs
Two sources publish an incubation period and they publish the same one. Seriously Fish: incubation lasts around 9 to 12 days at 24 to 25 C, 75 to 77 °F. Shrimpy Business: a 9 to 12 day incubation period. Aquarium Co-Op puts it in weeks instead, saying eggs hatch in about 1.5 weeks, which is the same figure in different units.
That is the only figure on this record all our sources agree on, and it is worth contrasting with our assassin snail record, where four sources give the hatching time and one of them is a month out from the other three.
On where the eggs go, Aquarium Co-Op describes fish that scatter eggs on floating plants, which is the same furniture station 03 asks for. These are not the killifish that need their eggs dried, and no source we hold suggests a dry incubation for this species.
How easy it is, and what the fry eat
Seriously Fish: relatively easy to breed, and in a well-decorated, mature species set-up fry may begin to appear without further intervention. Shrimpy Business calls breeding fairly straightforward.
The fry food is where all three sources converge on the same short list. Aquarium Co-Op: infusoria, vinegar eels, powder fry food and live baby brine shrimp. That is the same list our honey gourami and apistogramma pages carry, and it is the reason our brine shrimp guide exists.
The phrase to hold onto is species set-up. Seriously Fish’s easy breeding is in a tank with nothing else in it, and the same source has already said this fish does not make an ideal community fish. The two statements are the same statement: a mature, well-planted tank of ten clown killifish and nothing else is where our sources put this animal.
What this record will not answer
How long it lives
Two to three years per one source and up to five per another, with the two most technical sources publishing nothing. Station 04 prints the pair.
How many to buy
Eight to ten per two sources, or three to four by the ratio the third publishes. Both are on the record and they are not the same instruction.
A growth rate
Nobody publishes one, which is the usual answer on this site and the reason that row is blank.
Whether it belongs in a community tank
One source says not ideally and another names six tank mates. Station 05 prints both and checks the three we hold records for.
Whether the shrimp colony survives
Adults are not eaten and babies are, per the only source that addresses it. What proportion of a generation that costs is not something anybody publishes.
What Wikipedia would normally add
Nothing here. That article is a stub and publishes no size, water figures, lifespan or trade information, which is unusual for a record on this site.
Clown killifish questions, answered from the record
What is the right clown killifish tank size?
Five gallons on two sources, and about eleven on the third. Aquarium Co-Op asks for a 5-gallon nano tank or larger. Shrimpy Business asks for 5 gallons minimum with 10 or larger preferable. Seriously Fish gives no volume and asks for a base of 45 by 30 cm, which is roughly eleven gallons, and it asks for 8 to 10 fish in it.
How many clown killifish should be kept together?
Eight to ten, per Seriously Fish and Shrimpy Business, the first of which calls the species relatively gregarious. Aquarium Co-Op publishes no group size and gives a ratio instead, 1 male for every 2 to 3 females, which describes three or four fish. The record prints 8 to 10 and notes that the two figures are not the same kind of figure.
How many clown killifish in 5 gallon and 10 gallon tanks?
Our sources do not answer that directly and the arithmetic is uncomfortable. Two of them accept a 5 gallon as the minimum tank and two ask for a group of 8 to 10, and the third figure, Seriously Fish’s 45 by 30 cm base, is about eleven gallons for that group. A five gallon is the smallest tank any source allows and the ten fish are what the other two sources ask for, so the honest reading is that a five gallon suits fewer fish than the group figure and no source prints the number. How many clown killifish in 10 gallon is the easier half: ten gallons is what Shrimpy Business calls preferable and it is close to the 45 by 30 cm base Seriously Fish asks for with a group of 8 to 10 in it, so a ten gallon is the first size at which the group figure and the tank figure agree.
What water do clown killifish need?
68 to 79 °F, pH 4.0 to 7.0 and 18 to 143 ppm hardness. The pH floor of 4.0 is the second lowest on this site, after our kuhli loach record at 3.5, and the ceiling of 7.0 is the part most keepers will meet first, because it means the fish tops out at neutral. Seriously Fish and Shrimpy Business both publish 4.0 to 7.0; Aquarium Co-Op publishes no pH at all.
Do clown killifish need a heater?
Less than most fish here. The published bands start at 67 or 68 °F, which makes this one of the few records on this site that a warm room can hold without one. Only our guppy record at 63 and our goldfish record at 68 start as low. What the record cannot tell you is whether your room stays there, and every source publishes a ceiling of 79 or 80.
How long do clown killifish live?
Two sources and a factor of two. Aquarium Co-Op says about 2 to 3 years. Shrimpy Business says up to 5 years. Seriously Fish and Wikipedia publish no lifespan at all, which is why the row carries the whole span, 2 to 5 years, rather than a figure.
What do clown killifish eat?
Small live and frozen food, with dried accepted. Seriously Fish: this species accepts dried foods but should receive daily meals of small live and frozen fare such as Artemia nauplii, Daphnia, Moina and grindal worm. Shrimpy Business calls them micro predators that may accept dried foods but will most appreciate live and frozen. Aquarium Co-Op names tiny floating foods and slow-sinking foods including live baby brine shrimp and frozen cyclops.
Will clown killifish eat shrimp?
Adults no, babies yes, and one source draws the line exactly there. Aquarium Co-Op: clown killifish do not seem to eat adult dwarf shrimp, but baby shrimp are fair game. Our cherry shrimp record carries an adult of 30 to 40 mm whose young hatch at about a millimeter, so both halves apply to the same tank, and our grid marks the pairing a caution.
How do you tell a male clown killifish from a female?
By the tail. Aquarium Co-Op: male rocket killifish have brightly colored tails, whereas females have a clear tail. Seriously Fish and Shrimpy Business both describe males as more colorful with longer fins, which needs two fish side by side; the tail can be read on one.
How does clown killifish breeding work?
They scatter eggs on floating plants and the incubation is the one figure our sources agree on: 9 to 12 days at 75 to 77 °F per Seriously Fish, 9 to 12 days per Shrimpy Business, and about 1.5 weeks per Aquarium Co-Op. Seriously Fish calls breeding clown killifish relatively easy and says that in a well-decorated, mature species set-up fry may begin to appear without further intervention. Fry take infusoria, vinegar eels, powder fry food and live baby brine shrimp.
Do clown killifish eggs need to be dried?
Nothing our sources publish suggests it for this species. They scatter eggs on floating plants and the eggs hatch in 9 to 12 days in the same water, per two sources. The dry incubation associated with some killifish is not something any source we hold applies here.
Are clown killifish good community fish?
Our sources disagree. Seriously Fish, in its own spelling: peaceful with other species but does not make an ideal community fish due to its small size and somewhat specialised requirements.
Aquarium Co-Op names celestial pearl danios, Norman lampeye killifish, chili rasboras, pygmy cory catfish, snails and other nano species. Of those we hold records for the chili rasbora and the corydoras, both of which share water with this fish, and for snails, which do not: our nerite snail record starts at pH 7.5 and this record stops at 7.0.
Do clown killifish jump?
Aquarium Co-Op puts it as a condition rather than a warning: they will not jump out if you keep a tight lid or hood with all of the gaps covered. No other source we hold raises it. It follows from the layer, since this is a surface fish and already at the top of the water.
What is the scientific name of the clown killifish?
Epiplatys annulatus, Boulenger, 1915. Wikipedia lists four former names, Haplochilus annulatus, Aplocheilus annulatus, Panchax annulatus and Pseudepiplatys annulatus, and Seriously Fish notes that the genus Pseudepiplatys is now considered invalid. The fish is also sold as the rocket killifish, the clown killi and the banded panchax.
What a clown killifish needs that a nano tetra does not
Three things our sources ask for, and one of them is a lid.
- A tight lid with the gaps coveredone source keeps them from jumping out that way
- Floating plants, and low flowa surface fish from lushly planted still water
- Live or frozen food dailydried food is accepted by two sources and sufficient to none
Every item our records ask for is gathered on the tank setup topic.
Nothing here is a paid link. It is the shortfall between what this record asks for and what a boxed kit contains.
How this record was compiled
- By
- Verified
- Sources
Seriously Fish, Epiplatys annulatus, Aquarium Co-Op, clown killifish care, Shrimpy Business and Wikipedia, Epiplatys annulatus
- Conflicts
Printed above: one source gives the lifespan as 2 to 3 years and another as up to 5. Our sources also disagree about the group, at 8 to 10 fish against a ratio describing three or four, and about whether this is a community fish at all
- Blanks
Growth rate stay empty until a source we trust states them
- Not recorded
A growth rate, because nobody publishes one; and a lifespan from either of the two most technical sources, both of which decline to give one