How big does a tank have to be for catfish?

The size of the tank you need for catfish will depend on the species of catfish you have. Some catfish can grow quite large, while others stay relatively small. Here are a few general guidelines for tank size:

- Small catfish (up to 6 inches): A 10-gallon tank is a good minimum size for small catfish. This will provide them with enough room to swim and explore.

- Medium catfish (6-12 inches): A 20-gallon tank is a good minimum size for medium catfish. This will give them plenty of room to grow and move around.

- Large catfish (over 12 inches): A 40-gallon tank is a good minimum size for large catfish. This will provide them with enough space to swim comfortably and to hide if they feel stressed.

It's important to keep in mind that these are just general guidelines. Some catfish may need more or less space, depending on their individual needs. If you're not sure how much space your catfish needs, it's always best to err on the side of caution and choose a larger tank.

In addition to tank size, you'll also need to consider other factors when setting up a tank for catfish, such as water temperature, pH, and filtration. Catfish are generally hardy fish, but it's important to provide them with the proper environment to thrive. If you have any questions about caring for catfish, be sure to consult with a qualified aquarium specialist.