Experienced aquarium owners know they should research different fish species before putting them in their tanks. Some fish are very aggressive and will fight with or eat their tank mates. Meanwhile, ...

Some pet tropical fish are naturally placid, while others are fearsome predators.

This octopus behavior might look funny at first glance, but it reveals how evolution solves complex problems in unexpected ways.

Peaceful tanks look great, but they’re not always the most exciting. Some fish bring a lot more drama, and for hobbyists who know what they’re doing, that can actually be the fun of it. These ...