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Main Index > Detailed Fish Profiles > Miscellaneous species > Clown knife
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This page will give a completely detailed profile of the selected fish, from A to Z. The profiled fish will be chosen randomly by Badman, and will come from the complete genre of tropical fish. New profiles are added on a regular basis. If you would like to submit a profile for the site please contact me. Don't forget to let us know you experiences with this fish by filling out the




photo courtesy of Aqualand pets plus

Chitala chitala



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Please remember that the following comments are personal experiences and may or may not apply to your setup. Use them as guide to help better understand your fish, like us all individuals will behave differently under different circumstances.


From: walkingcrow
In my experience with clown knife fish, they are very territorial. Their mouths are very large and they grow at a very fast rate. I don't recommend feeding live foods because you never know what diseases that they are harboring. I always use frozen silverbacks or other type of minnow that is safe for aquarium fish. I use a set of wire tongs to feed them with. I have also fed them pellet foods with no problems. This fish gets very large and can only be housed in a 55g. tank until they are about 12 inches in length. As with any fish, keeping them is to small of a tank will stunt their growth, not just on the outside but even their internal organs will have stunted. Therefore, shortening their lifespans altogether. That is why they say that juvenile specimens usually don't live to maturity, which is about 30 inches in length. The two I have are not shy at all, they are not nocturnal either, they are very active throughout the day and night. Dither fish, such a giant danios may be okay to help keep the fish from feeling to shy, but eventually even the danios will be eaten. A good tank mate choice would be Silver dollars, or pacu, but housed in a tank no less than 100gallons. Any fish that is smaller than they are and they will become dinner. Snails will be dinner as well or any other catfish. A very large pleco could be okay, but even then water changes are still important due to the fact that plecos do not really eat all waste. By feeding Clown knives live foods it is causing more waste produced in the tank, and a weekly water change should be done to ensure that ammonia levels do not rise to poison or any dramatic ph or nitrate levels. I would recommend only experienced and knowledgeable fishkeepers to house this fish.
From: -luc
Oh boy, what did my fiancé and I get ourselves into? Our clown knife is about 6 inches long. We went to the store to get pet supplies, he saw the fish and just had to have it... So of course we ended up getting it. It now sits in our 55 gallon tank. We found out after a couple days of having him that he likes guppies. We bought 2 dozen feeders and only 7 remain after one night. Our knife is housed with a pictus catfish, an iridescent shark, a bumble bee catfish, a spotted green puffer fish, a large comet, a 2ft. pleco, a long finned rosy barb and a dwarf gourami. They get along fine. The knife and the puffer seem to be "friends" and always following each other around. The knife is semi active during the day and very active at night. While we were doing a water change he would be right there near our hands. It was pretty cool. He is awesome to watch hunt. I didn't realize how big his mouth was. I'm hoping that he wont outgrow our 55 gallon anytime soon, although it sounds like we need to put our other fish into another tank in a couple of months.
From: Dave
I have two clown knifes for about a year now they have grown from 3" to 14+ I used to feed my clown knifes feeders but that became way to expensive so did fish food so I turned to other foods. I have 4 cats and they love to watch the fish more then I do. This idea came to me when I ran outta of fish food and had no money and tons of dry cat and dog food. I now feed my main tank cat food or dog food. I have 2 clown knifes in the main tank along with 3 Colombian sharks and 3 oscars that are 5 years old. My all eat the cat food like crazy. The Colombian sharks or white tipped catfish prefer the dog food over the cat food for some reason. I advise you give it a try.
From: Marco
I've had my clown knife for about 7 mo.s now. He's grown about 10 inches in this time. I have him in a 55 gal. for now. Soon I will transfer him into a 135 gallon,when I feel he can handle my oscars(which are all over a foot long.) The clown knife is a voracious predator that eats any fish he can fit into his cavernous mouth! I have to be careful not to overfeed him. He doesn't stop hunting until every goldfih is gone!
From: grembo
Mine is easily 2 ft long at about 3 yrs of age. Housed in a 150 gallon tank. Seems to be very peaceful although I haven't been able to introduce any other fish for any length of time. Anything that will fit in it's mouth will be tried. It recently killed my 6 inch bristlenose pleco. Doesn't seem to be interested in pellets. I feed about 4 goldfish per day although more will be eaten if introduced. Isn't shy at all. It even lets me pick it up when moving between tanks is needed. Eats nightcrawlers if given, although not as enthusiastically as live food. I've found info on the net stating that they grow to lengths of 6 ft, though that is probably in the wild. Is very friendly and gets very excited when I approach my feeder tank, even shivers in anticipation.
From: gemin8888
My clown knives are still housed in a 55 gallon tank after almost two years. They eat live goldfish, frozen blood worms, some flakes foods, and pellet foods as well. The two knives get two fish about every other day, the other days they get to feed on something other than live fish. Though I do highly suggest to quarantine your live feeder fish and monitor them for any disease or parasites before feeding them to your knives or other predatory fish. Only to ensure that you do not pass it on to the other fish. Water changes are definitely important to maintain ammonia and nitrate levels. I found that dither fish, such as giant danios are very very quick fish and the clown knives cannot keep up with them at all. Also large silver dollars or pacu can become tank mates. However I do stress the fact that these fish came grow to a length of possibly 4 feet!!! Mine are only 12 inches and are being put in their final home in the next few months, which is a 300 gallon tank. These fish will eat anything they can fit in their mouths, they use echolocation to track their prey. Mine come out all hours of the day and night, so despite what they say about them being nocturnal it doesn't seem to be totally true with mine. They have many hiding places and choose not to use them. These are very beautiful fish, can be territorial as they get larger, while they are still young they tend to hang around each other alot, but as they grow larger, they may get agressive towards one another, or one will dominate over the others.
From: J Shcneider
I purchased a pair of sub adult knives , they are about 12-14 inches in length and about 5-6 in height. Big fish!!! I am unaware of how to sex them but the two I bought were raised together so they really are if you can say it a mated pair, they will not leave each others side. Very peaceful. I house them in a 180 gallon tank with Silca sand substrate and round smooth rock boulders, also the tank is covered in duckweed and large amazon sword plants, the other fish include a 13 inch Lungfish, 12 inch marbled Pim catfish, 4 5 inch silver dollars, everyone gets long fine, the only troubles I had was when I have a common 10 inch pleco, he would attack everything in the tank and he was relentless about it. My meanest fish, the Pim Cat still has scars from the Pleco. All in all if you have a big tank get this fish, if not, then its really not fair to the fish at all as they do grow very large. As for diet, my clowns have been fed pellets from day one, and frozen shrimp, never have they had live food!!!! So do not listen to all the hype about having to feed live food, all my fish are on frozen or pellets, even ones that were raised on live goldfish.
From: Shannon
I have two clown knife fish, I have had them for almost a year now. In the beginning, they fed off of blood worms,adult brine shrimp, some pellet food as well. Once they they grew from 3-4 inches to about 6 inches, they refused it. So I switched to minnows, occasionally they will take large clumps of beef hearts. I do not have the typical knife fish, who are shy and only come out at night. Mine are always out and about even with the lights on. They have plenty of hiding spaces, but they choose to swim with the lights on or off. They are peaceful fish, not aggressive at all, but they will try to fit anything they can in their mouths to eat. I house mine with the fastest fish I could find, which is the Giant danios, they are about 4 inches long. I also have a pleco that they never bother with, and I have a female convict in the tank as well. They get along fine. As long as the fish they are in there with are very fast swimmers or they are large enough so they cannot eat them, they are fine. My knives have been growing about an inch or so each month, they eat about 4 to 5 minnows or one small goldfish every 2nd to 3rd day. I keep my feeders in a separate tank to make sure they stay disease free, so that I can keep the clown knife tank healthy as well. Getting feeders from a local fish store, you know they are probably going to be healthier than at a chain pet store. These are great fish if you have enough space to house a very large tank, since they grow so large. Watching the spots and stripes change on them as they grow, I have one that has alot of very defined spots, many spots, the other one has a normal spotting pattern, big black circles outlined in white, very pretty fish. They are not shy at all and go crazy when I come close to the tank, the only time they seem to shy away from me is when I do water changes, as if they are upset because I disrupted their swimming patterns. So I keep everything in it's place after I am done the water change.
From: Andrew Wallin
I just recently purchased a 3 inch baby clown knife from our fish store. I did a lot of research on the fish and it's behavior before purchasing. I have it in a 55 gallon planted tank with lots of Jungle Val plants(ph 7.2, 76-78 degrees no trace of nitrite/nitrate/ammonia). one interesting behavior that I have noticed is that when I put frozen brine shrimp in the tank he will go into a hunting/stalking mode and will swim tail up to mimic the blades of jungle Val. he then slowly drifts up to a piece of food hung up on a leaf or rock and inhales it. I think I'm lucky that he will even accept frozen food from what I have been reading. He hasn't bothered his other tank mates at all either. I keep him with several gold dust mollies (these will breed feeder fish eventually) and a 4 inch blue panaque. The clown knife will even nibble on the algae wafers that I put in for the pleco! having a planted tank with plenty of hiding places I believe aids in making the clown knife feel more comfortable. Also my fish is still a juvinelle (perhaps a month or two old) so it still has it's stripes. hope this info helps out
From: Nimish
A beautiful, graceful fish.. Grows very fast. As I have read some people having problem feeding it, I know a few who have starved it to death. Before this happens the best idea is to dig up a small 1 feet corner in your lawn and gather some earthworms.. It loves the food that fills its mouth :). the mouth is unsuspectingly bigger so even if starting from smaller specimens (4-6 inches) do not keep fish smaller then 1.5 inches with it. You wont even find a trace of the smaller fish. I have had very peaceful experience with it except for kribensis which tried to harrass the wrong fish, ended up as dinner.

From: Ventoni
I have 2 clown knifefish. The first one eats beef meat while the other eats blood worms... I'm having a hard time feeding the other one because I want to train him for eating beef meat.

From: August
I just purchased a 3 inch clown knife and am having a time trying to get him food. I have a 1 foot arowana in the tank with him, yet he doesn't seem to be scared of him. They don't even fight. But I am trying to feed him guppy's and frozen shrimp. The problem is all the other fish eat it first, he still seems a bit scary. Does anyone have any good advice on how to make sure he gets his share. I am going to try and feed him at night when the others are less active. But still in all, he is a blast to have and to watch swim. I highly recommend one for the home aquarium.

From: Shereen
I have successfully raised a oscar and knifefish together with a tire tread eel and large pleco. They are a happy peaceful family. The trick is to get them young and near in size with the oscar a bit smaller. But with my second knifefish family the eel did not grow as rapidly and when I left the lid open one day the eel got chased by the clown and committed suicide by jumping out of the tank.....and the clown chased him. So beware they can and will get out!

From: Paul
I started w knife fish almost 7 years ago now...they grow very large and they eat small goldfish...they can be trained to get the food from your time I dipped my finger in the water and it thought it was food so it bit it...but they are very timid and shy...they don't attack other fishes...right now I have 2 in a 50 gallon tank...I plan to add an arowana next...the baby arowana that I have is in a 20 g tank but I will buy a new one soon...the knife fish is very hardy...even after 2 days of setting up the aquarium(of course after all the chemicals have been put in)...they could live with that...they are not so just takes them a couple of minutes to adjust!!!

From: Vonda
This awesome species is also legally blind! 'Tis true, that is why they are nocturnal animals, they send electrical pulses in the water (don't worry this can't hurt you) the pulses bounce off other fish in the tank in return the clown knife can determine the size of the other fish and weather or not it sizable to eat as food. They prefer the dark and/or well planted aquariums, watch they come out at night to eat! Also these fish can grow well over 3 feet long. Awesome fish not for all tanks though!

From: piva
I have a 20 inch clown knife. He's 2 inches thick and 6 inches tall. He was 9 inches when I got him 18 months ago. He eats an average of 200 to 300 feeder comets a week. He has a 125 gallon tank to himself, so I hope to grow him to 3 feet in length. These large fish make aggressive lunges to the tank surface, so make sure to secure the lids, and be ready for loud splashes late at night.







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