How to take care of Clown knife Fish?

We will talk about clown knife fish care in this blog post.We will also discuss important factors such as their habitat, types,lifespan,tank set-up, water parameters and healthcare, etc.Everything you need to know about clown knife fish care will be briefly discussed.


In this blog 

  • Key specifications of clown knife fish
  • Why is clown knife fish care important?
  • How many clown knife fish should you start with as a newcomer?
  • Habitat of clown knife fish
  • Types of clown knife fish
  • Different strains or colors of clown knife fish
  • General and physical attributes of clown knife fish
  • Clown knife fish lifespan
  • Clown knife fish tank set-up
  • Clown knife fish diet and feeding requirements
  • Clown knife fish healthcare and health conditions
  • Clown knife fish daily care and Bi-weekly care tips
  • Summary

How to take care of Clown knife Fish?

Daily care tips for clown knife fish

  • Clean aquarium glass daily.
  • Maintain pristine water conditions for both juveniles and adults, juveniles will die quickly if they don’t get the right amount of care.
  • Feed them small amounts twice a day, juveniles should be fed thrice a day to make sure they are not generating the biomass.
  • Always turn off the lights before feeding them.
  • Don’t overfeed them, underfeeding is fine but overfeeding is not good for any fish.
  • Maintain all the vital tank parameters for their growth and development.
  • Keep checking if all the equipment is in working conditions or not.
  • Avoid sharp decorative items in the aquarium.
  • If they are not eating anything or showing inactivity then consult a vet.

Bi-weekly care tips for clown knife fish

  • 10% water replacement should be done weekly.
  • 25-50 % water replacement should be done once in 2 weeks.
  • Filters and other tank equipment should be washed thoroughly to avoid any tank pollution.
  • Quarantine new tank mates for two weeks at least before adding them to the main tak to avoid various infections.

Key specifications of Clown knife fish

Scientific name Chitala ornata
HabitatConservation statusSouth east asia (Invasive species)Least concern category
Lifespan15 years (natural habitat)Between 8-15 years (captivity)
DietOmnivore (aquarium setting)Carnivore/Predators (original habitat)
Body sizeBody shapeColorSpecial trait
Sexual dimorphism
10-20 inches in captivityFlat and elongatedSilver grayBlade shape appearanceCan swim in backward directionsYes 
Another namesClown Knife fishClown night fish
Optimum temperatureOptimum pHAlkalinity75F-80F7.0-8.090 ppm- 180 ppm
TemperamentBeginner/ experienced Aggressive Experienced aquarium keepers
Care levelDifficult
Tank size and set-upTank type (Prefered)110 gallonsVery large planted tank 
Preferred plants/decorationsThick vegetation
CompatibilityOther peaceful mates
Number of knife fish species found Number of knife fish -50 species total
BreedingDifficult to breed in tank settings

Why is clown knife fish care important?

They are shy when you get them home for the very first time but after some days they get familiar with the surroundings and all their shyness goes away.

Along with their shyness they are picky eaters,so their feeding time and how to feed them along with the vital parameters all should be kept in consideration for caring for these guys. 

How many clown knife fish should you start with as a newcomer?

If you’re a newcomer then let me tell you they get bigger in size when they get matured, so get a large tank to house them.And try not to keep two males together, as they tend to get aggressive and hurt each other.

They are actually not meant for home aquariums because they need a great amount of care because they get large in size and need frequent tank cleaning of that bigger tank.

So in my opinion don’t get these guys if you can’t maintain them and all the vital parameters along with tank filtration.

Filters are going to cost you like anything and filtration is a must in their aquarium.Juveniles are 3-6 inches in length for sale.

Keep in mind:

  • Don’t get confused while buying them,original clown knives will have black spots, circular markings on their body and they are true clown knife fish.
  • Chitala chitala also looks the same and people confuse them with ornata.

Habitat of clown knife fish

Clown knife fish are found in lakes,backwaters and river basins in Southeast asia. They are widely distributed in those areas.

Types of clown knife fish

  • Clown featherback
  • Spotted knife fish
  • Albino clown knife fish

Different strains or colors of clown knife fish

  • Silver gray 
  • Golden colors
  • Albino
  • Knife fish with bars

General and physical attributes of clown knife fish

  • Clown knives are scaleless fish.
  • Body type- Knife blade type. 
  • Striking feature- large spots on their body (circular markings)
  • Clown knives can swim backward with the help of their bottom fin.
  • Caudal and anal fins are fused to form a single fin.
  • Male clown knives are larger and slimmer than females.

Clown knife fish lifespan

  • Clown knife fish can live between 8-15 years in aquarium settings.
  • Feed them a proper nutritional diet and maintain the tank conditions by monitoring the vital parameters for their better survival and longevity.

Clown knife fish tank set-up

Tank sizeLight intensitySubstrateWater parametersTemperatureTank plantsTank mates

Tank size for clown knife fish

Tank size and shape is the most important requirement for clown knife fish, because this fish grows very quickly and won’t be accommodated in a smaller sized tank.Overcrowding can stress them if kept in smaller tanks with tank mates.

  • Clown knife fish need a large tank with sophisticated equipment setup in their tank.
  • Bigger the better goes with clown knife fish tanks because they grow quickly.
  • A 110 gallons/500 liters tank or even larger will be the best size for housing them, because they reach upto 3 feet in length.
  • Tank shape- A horizontal shape tank would be better.
  • Clown knife fish need a lot of hiding spots in their tanks.
  • Clown knife fish mostly spend their time in the middle and bottom of the tank.
  • Clowns are great jumpers and can escape out of tanks, so it is advised to cover their tanks with tight lids.

Light intensity for clown knife fish

Clown knives are nocturnal predators naturally and they prefer dim lighting especially during feeding time.

  • Subdued lighting is preferred.
  • Day-night cycle is also preferred.
  • Clown knives are nocturnal fish and mostly eat when the lights are turned off.
  • Clown knives are great jumpers, but won’t jump in subdued lighting.

Substrate/decorations for clown knife fish

  • Sand or gravels can be used as a substrate
  • Gravels should be cleaned with a good gravel cleaner,because if not cleaned well they will also develop bad bacterias which can ruin their health.
  • Rocks,pipes and caves can give them good hiding spots to feel secure when threatened.
  • Clowns need rocky substrate for spawning.
  • Don’t use decorative items in their tank. 

Water parameters for clown knife fish 

Clown knife fish are hardy species and can withstand a wide range of water conditions.But they are sensitive to poor water settings.

So it is advisable to maintain pristine water condition in their tank for their better survival in home aquariums.They can survive both in freshwater and seawater.

  • Proper oxygen flow should be maintained in the tank.
  • Ammonia-zero
  • Nitrate-lower than 20ppm
  • Nitrite-zero
  • pH-7.0-8.0
  • Alkalinity-90 ppm- 180 ppm
  • External filter system- canister filters is important in their aquarium
  • Water changes should be done weekly or once in 2 weeks.
  • It’s difficult to change water in such bigger tanks, better to get an automatic water changer system.

Temperature for clown knife fish

Temperature maintenance in aquariums is extremely important because that decides the metabolism of an organism and their growth.

If this parameter is not maintained well the fish might not survive well in the home aquarium.

  • Clown knives do well in warm water conditions.
  • Optimum temperature- 75F-80F
  • Heaters can be used if needed to maintain the right temperature.

Tank plants for clown knife fish

Add a lot of vegetation (thick vegetation) in the tank for them to feel secure and stress free.Heavy plantations will help them even in the spawning process.

Although spawning in aquarium settings is a bit difficult.If some aquarists are planning them to breed, they need a lot of plant covers to dim the light for the spawning process.

  • Rooted plants
  • Driftwood
  • Aquatic plants
  • Floating plants

Tank mates for clown knife fish

Clown knives get aggressive with their own species when they reach adult stage,so avoid them.

Add tank mates larger than their size, because anything smaller goes directly into their mouth.They are piscivores and have the habit of eating smaller fish in the wild.

Compatible tank mates:

  • Large sized cichlids
  • Large sized gouramis
  • Synodontis genus catfish
  • Tinfoil barbs
  • Angelfish
  • Iridescent shark

Clown knife fish diet and feeding requirements

Clown knives are shy in nature and it is quite difficult to feed them because they are carnivores in the wild and prefer to eat live food only.

Being nocturnal fish,they prefer to eat when the lights are turned off.Keep rotating their diets for better results.

Feed small amounts twice a day but never overfeed.Feed them protein enriched diet.

  • Blackworms
  • Frozen cubes of bloodworms
  • Ghost shrimps
  • Feeder fish- Avoid feeder goldfish
  • Beefheart (favorite)
  • High quality commercial pellets
  • Flakes -A big no to flakes
  • Some clown knife keepers feed them veggies too.(i am not sure if they enjoy eating vegetables or not)

Clown knife fish healthcare and health conditions

Clown knives are scaleless fish and due to poor water quality they are prone to get various diseases.So it’s very important to maintain pristine water conditions in the tank.

If the water is not changed on time then some harmful bacteria will generate in the tank and will make your fish inactive and sick.You can use UV sterilizers to keep infections at bay.

  • Ich/white spot disease
  • Some skin related infections, since they are scaleless fish.
  • Overfeeding can cause a lot of health problems, so it’s advisable to underfeed your pet. 


  • Clown knife fish are sold as exotic fish in the pet shops.
  • Aggressive and nocturnal predators.
  • Clown knives look so unique when they swim around in the tank.
  • Clown knives are not expensive but their maintenance is really expensive.
  • Clown knives are suitable for large aquariums
  • Not a beginner fish because of their big size and feeding habits.
  • Valued as food fish and ornamental fish

Frequently asked questions on clown knife fish care

Are clown knives sensitive to medications?

Yes, clown knives are sensitive to medication.Always consult a vet before giving them any kind of medications.

What are the three important things to care for them in an aquarium?

The three important factors you need to keep in mind are, Tank size , feeding behavior, and filtration practices.