"Setup
They grow to an adult maximum of only 4 inches long, so a 20-gallon tank or larger will give them plenty of room to grow, thrive, and behave much as they would in nature. Outfit this tank with plenty of foliage and wood. Living plants such as swords, hornwort, anacharis, or species from the Cabomba genus work well and provide plenty of vertical structure within the tank. The main purpose of structure within the upside-down catfish tank is to simulate the dense streams from which these cats come, for they tend to fare better in naturalistic surroundings."
source:
Upside Down Catfish
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