How to take care of Cowfish?

We will talk about cowfish 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 cowfish care will be briefly discussed.


In this blog 

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

How to take care of Cowfish?

Daily care tips for cowfish

  • When they release toxins, kindly discard all the sand, rocks and corals from the tank.
  • Aquarium should be cleaned regularly to avoid toxins and other harmful substances
  • They should be fed twice a day.
  • Can be trained to hand fed
  • Avoid feeding them on the surface.
  • Wear gloves while handling them as they release toxins.
  • Monitor temperature daily.
  • Check if all the tank equipment is in working conditions or not.

Bi-weekly care tips for cowfish

  • Water quality should be checked weekly 
  • While changing water, put them alone in a separate tank.
  • Quarantine their love food for 2 weeks before feeding them to avoid infections.
  • Clean decorative items and tank plants once a week.
  • Quarantine new tank mates before adding them to the main tank.

Key specifications of Cowfish

Scientific name Lactoria cornuta
Conservation status
Indo-Pacific regionSaltwater fishNot evaluated
Lifespan2-8 years
Body sizeBody shapeColorSpecial traitSexual dimorphismVenomous 16-20 inches longBox shapedYellow sand, blue and whiteOstraciiform swimmingNoYes
Another namesLonghorn cowfishHorned boxfish
Optimum temperatureOptimum pHWater hardnessSalinity/specific gravity75F-82F8.1-8.48-12 dKH1.020-1.025
TemperamentBeginner or experienced PeacefulExperienced fishkeeper
Care levelDifficult
Tank size and set-upTank type (Prefered)200-250 gallonsReef tanks
Preferred plants/decorationsMarine plants
CompatibilityOther peaceful fish
Number of cowfish species found Four (longhorn cowfish 25 species)
BreedingPelagic breeding

Why is cowfish care important?

Cowfish are known to be one of the cutest aquarium fish.They are a cute but fatal kind of fish because they release a neurotoxin, ostracitoxin when stressed and threatened,which can kill tank mates and cowfish its very important to care these pets with utmost care and caution.

How many cowfish should you start with as a newcomer?

I would suggest getting one cowfish if you’re a newcomer, and while introducing them to the aquarium, avoid keeping the bag of water in the aquarium ,because they  might be stressed out from shop to home and would have released toxins which can kill them and others in the tank. 

Habitat of cowfish

Cowfish are saltwater fish and are found in Indo-Pacific regions.They can be seen in lagoons,reefs and estuaries.They are now found in Australia too.

Types of cowfish

  • Honeycomb cowfish- Bony fish have the ability to change color in the blink of an eye in order to protect themselves from their predators.
  • Long-horned cowfish/ horned boxfish
  • Diaphanous cowfish or round-Belly cowfish
  • Lactoria fornasini/thorny-back cowfish- Most poisonous cowfish
  • Camel cowfish or humpback turretfish
  • Scrawled cowfish

Different strains or colors of cowfish

  • Honeycomb cowfish-blue,yellow,gray or green.
  • Juvenile cowfish are more colorful than adult cowfish.

General and physical attributes of cowfish

  • Cowfish can grow upto 16-20 inches in captivity.
  • Cowfish are recognized by their long horns that protrude from the front of its head.
  • Having no pelvic skeleton,cowfish lack pelvic fins,and have a unique method of swimming, called ostraciiform swimming using wave-like movements of their body and tail, which causes them to look as if they are hovering.
  • Defense mechanism-Cowfish have typical spines over their eyes, those little horns may frighten predators from gulping them.
  • Cowfish are slow-moving fish due to their awkward body shape.
  • Cowfish hunt with the jets of water.

Cowfish lifespan

Pet cowfish can live between 2-8 years in captivity.If the water conditions are excellent they will have a longer life but they may die off soon if pristine water conditions are not maintained in their tank.

Cowfish tank set-up

Tank sizeLight intensitySubstrateWater parametersTemperatureTank plantsTank mates

Tank size for cowfish

  • 200-250 gallons in size,depending upon the cowfish species.
  • Leghorn cowfish need tank size of 250 gallons 
  • Smaller cowfish can be kept in small sized tanks but keep in mind they grow really very fast and soon you have to shift them to bigger tanks.
  • Bigger the better is the requirement for a cowfish tank.
  • Cowfish need plenty of space and lots of hiding space in their tank.

Light intensity for cowfish

  • Low light or subdued lighting is better.
  • Bright lights can cause stress.
  • Standard aquarium lighting is preferred.
  • Not much information is there about their lighting preferences.
  • Kindly consult the pet shop owner regarding how much light they need in their aquarium.

Substrate and decoration for cowfish

  • Live rocks and with algal growth on their surface.
  • Cowfish  don’t need sand or gravel but you can use live sand.
  • Cowfish eat by blowing their substrates to find food there.
  • Decors suitable for saltwater tanks are dead corals,coral inserts, false coral,castles and skulls.
  • Avoid keeping edgy decorative items in their tanks.
  • Always clean decorative items to avoid infections in the tanks.As they harbor bacteria in them.

Water parameters for cowfish

Cowfish need great water quality to thrive well in aquarium settings:

  • Pristine water conditions
  • Optimum pH – 8.1-8.4
  • Water hardness – 8-12 dKH
  • Salinity or specific gravity – 1.020-1.025
  • Less turbid water like their natural habitat.
  • Water movement- Slow-moderate (calm water)
  • Filtration system-Effective filtration system with slow water currents to remove the bioload they generate because of their heavy appetite.
  • Sudden movements can cause stress to cowfish
  • Cowfish are slow swimmers and won’t appreciate strong water currents in their tanks.

Temperature for cowfish 

  • Water temperature should be maintained properly with the help of a thermometer to avoid unnecessary fluctuation.Fluctuation could be fatal to them.
  • Optimum temperature – 75F-82F

Tank plants for cowfish

Choose tank plants which can tolerate saltwater conditions.

List of suitable saltwater tank plants for cowfish:

  • Seagrass
  • Mermaid’s fan
  • Halimeda
  • Red mangrove
  • Spaghetti algae also known as chaeto,great choice for beginners 
  • Red Gracilaria Algae
  • Green Finger Plant.

Tank mates for cowfish

Cowfish tank mates should be chosen wisely because during stress they tend to release poison which may not be good for other tank mates.Don’t keep them with aggressive eaters.

Young cowfish can be kept with tank-mates but adult cowfish do better in a solitary tank.

Suitable tank mates:

  • Tangs
  • Batfish
  • Clownfish
  • Blennies
  • Basslets
  • Hogfish
  • Dartfish
  • Angelfish (large and dwarf)
  • Cardinalfish
  • Chromis
  • Butterfly Fish
  • Wrasse
  • Anthias

Cowfish diet and feeding requirements

Cowfish are omnivores and prefer both meaty and vegetable based diets.Feeding cowfish is a bit difficult.

  • Feed them small size meaty food.
  • Cowfish eat at a very slow pace,so wait for them to finish their bites and give them sufficient time to complete their meals.
  • They take time to adjust with the prepared food.
  • They should be fed twice a day
  • Avoid surface feeding because of buoyancy issues.
  • They can recognize their owners and can be hand fed.
  • Overfeeding should not be done.
  • They eat a lot and increase the bioload in the tank.keep in mind to remove their uneaten food everyday to avoid tank pollution.

List of their favorite food:

  • Finely diced meaty food-Dried brine shrimp,mysis shrimp,Live gut loaded brine shrimp,chopped table shrimp
  • Chopped squid
  • Clam
  • Mussels
  • Frozen food
  • Marine algae
  • Seaweed
  • Sponge based food

Cowfish healthcare and health conditions

  • Cryptocaryon or marine ich or white spot parasitic disease- Use copper based medicine by consulting your vet to treat their marine ich. 
  • Lymphocystis-A viral disease,there is no treatment for this,the only thing which is important is maintaining the pristine water conditions, avoiding temperature fluctuations and feeding them a proper diet.
  • Buoyancy problems due to surface feeding,so avoid feeding them on the surface 


  • These goofy looking fish may look silly, but they can actually secrete a toxin when distressed.
  • Produce a deadly ooze that seeps out in a toxic cloud all around itself.
  • Cowfish are slow and awkward swimmers.
  • Cowfish can survive well with peaceful tank mates.
  • Cowfish have the habit of picking anything and eating whatever is near them,so avoid keeping things which are sharp and edgy.
  • Cowfish are always curious and have the habit of investigating their tanks.
  • Cowfish are a bit difficult to care for and are not a beginner marine fish.

Frequently asked questions on cowfish care

Can a cowfish live in freshwater condition?

Cowfish can tolerate freshwater conditions.

Are cowfish reef-safe?

Cowfish can be kept in reef tanks with lots of caution, because they have the habit of nibbling tubeworms.

Are cowfish aggressive in nature?

Cowfish are peaceful in nature but release a toxin under stress,which has the potential to kill other tank mates including their own kinds.