Which type of fish would not be good for an aquaponics system?

• A. Clownfish
• B. Koi
• C. Tilapia
• D. Catfish

Answer: (A)

In aquaponics, matching the fish to the system’s water conditions is essential. Clownfish are a tropical marine species that require saltwater and stable salinity, which is very different from the freshwater environments most aquaponics setups use. Mixing a saltwater species into a typical freshwater system would demand an entirely separate, properly managed seawater setup and additional equipment, making it impractical for standard aquaponics. The other options—tilapia, catfish, and koi—are freshwater species that tolerate the water quality and temperature ranges common in aquaponics, and they’re commonly raised there because they adapt well and provide reliable nutrient input. So clownfish wouldn’t be a good fit for a standard aquaponics system.