I have kept a variety tropical fish for over 50 years. With the exception of roseline sharks, also called red-lined torpedo fish or barbus denisonii, Congo tetras are my favorite mid-sized schooling fish. They are hardy, active, and non-aggressive to other smaller fish. The male coloring is captivating with its unique pattern of pastels. Currently, I have a school of 3 males and 2 females that get along well with a large school of primarily male cherry barbs as well as a large number of different rainbowfish. However, I suspect almost anything would look good with them. Fifteen years ago I had a large display tank with 15 Congos and 15 clown loaches. With the exception of a tank bottom consisting of colorful marbles, the tank was bare. The congos were non-stop motion at the top; ditto for the loaches at the bottom. At night, it could be illuminated with a subdued bluish light. I envision that those are the kind of tanks they'll have in the next life...at least I hope so.
I love these beautiful fishes and have 5 of them currently. Have been keeping these beauties for 2 years. They are very peaceful giants who do not disturb their tank mates. They love to eat insects, so do drop in some ants you caught from your garden or around the house if you can. Their scales will show a really nice colouration and good shine after feeding on insects. They are insectivores in the wild. Temperatures if kept from 23-27°C would be just great for them, and you can see them swimming freely. They are a little shy at first, but feed them at regular times, or at cues like you just switched on the light will familiarize them. You will soon see them swimming towards you at the time to eat with no shyness at all!
I purchased 10 Congo Tetras about 1 and a half years ago and I have them placed in a tank with a pair of Pelvicachromis pulcher (Common Krib) and 3 Pantodon buchholzi (African Butterfly Fish). They are thriving in the tank at the moment, as I am constantly doing 15% water changes every week, and have a drip system put in my tank. These fish are very quick, but don't pose much of a threat to other fishes. In fact, they are rather timid unless kept in schools. They make a great asset to an African themed community tank and will certainly catch the onlookers' attention, with their vibrant colours and erratic movements.
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