This fish grows to be very large and I would suggest at least 800 liters. It is best to feed it live fish, bloodworms and, for the large adult, crayfish. I keep one in a tank with an Oscar, pleco, red bellied pacu, and a silver dollar they get along just fine. The pacu and knifefish are best friends. They require heavy filtering, for they are very messy eaters.
I have two 25 cm clown knifes in my 540 L tank and I love them to bits. I have fed them on frozen fish from the day that I got them. I just want to say they do eat as much as they can in one sitting...but I have noticed that when they get back to their hiding place they regurgitate some of it and then feed at a slower pace.
I bought a clown knifefish in March and he was 8 cm. Now in November he is 31 cm. He has grown very fast and is a great fish. He is very intertaining to watch at night when he swims and hunts for feeders. They are beautiful swimmers and swims backwards sometimes. He is not very aggressive unless another fishes get by his food. He is fed shrimp, krill, shrimp pellets, and feeder goldfish (feeders once a month). He shares his tank with 23 cm and 13 cm bala sharks, and a 16 cm Senegal bichir. He has his own cave on one side of the tank, which he stays in most of the day. When he comes out it is usually to turn around or go to the top for air. Clown knives are great fishes to have, but get very big.
I was thrilled when my generous friend gave me a 30 cm Clownknife. It seemed to integrate seamlessly with the community of Black Angel, Gourami, Catfish, Climbing Perch, Cichlid and comet goldfish in my 360 L tank. The Clown carried an exquisite grace in gliding movement and wore an aura of pride and authority. During daytime it hid in a rock-cage and only came out during feeding frenzy. It seemed to command the respect of all other fish, though all others loathed the presence of the bullhead catfish. When this short-sighted character swam by poking around with its whiskers, all other fish avoided this insane personality like plague with utmost disdain for the bottom feeder. Soon to my rude surprise, my colorful comet goldfish and precious small cichlid were disappearing one-by-one on a regular basis. Determined to discover the Spanish inquisition myth in my tank, I checked my fish tank one midnight with a flash light--Oh my! The eyes of the Clown were like carís head-beam reflecting my flash lights. Prowling like a jaguar, Clown was sneaking up behind every fish to size them up. When it came to comet goldfish, it opened its mouth: Bam! Wham! Kabum! Kapow! The poor comet was gone in 4 scoops! It sent the rest panic running for cover! This Clown had a deceitfully big mouth that could match that of a large-mouth bass. I left the crime scene with absolute amazement and newfound awe for my Clown. No one mess around with my royal Clown your highness.
When I told my friend, he got that smug look on his face. He gave me a pair of large pink Tilapia. This pink pair seemed to settle in well in a short while, but I didn't realize that a war was looming on the horizon until it was too late. The Tilapia were about to breed and they were fiercely contesting the Clown's rock-cage territory for breeding ground. The fierce battle ensued-- Although far-surpassed in aggressiveness defending its territory fighting 1-against-2; the Clown's Monroe smooth skin were no match against the Tilapia's armored-vehicle thick scale. The Clown successfully defended its turf and repelled the Tilapia. The pair had to settle for the corner lot, but the Clown was severely bruised and it died 2 days later. Disheartened, I donated my large tank and all my fish to my generous friend.
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