FAHAKA PUFFER (Tetraeodon Lineatus)

A generally aggressive and intolerant species that really should be kept alone. Its beak-like mouth can easily bite chunks from other fish, or in extreme cases rip them to pieces. If you decide to take the risk you will need a huge tank, and tankmates that swim too quickly for the puffer to catch them easily.

It is also very aggressive towards conspecifics. Some aquarists have had success keeping it in groups, but to attempt this an enormous tank is required. The fish will still bite one another and fight, no matter how large the tank, so “success” should be regarded as them not murdering one another!

https://www.seriouslyfish.com/species/tetraodon-lineatus/