Why do freshwater fish dart around their aquarium?

Answer by  Znufoc01 (227)

This is perfectly normal for many types of fish, such as Danios and Tetras. They are just very active. Freshwater fish that dart around are commonly found in large schools, so it might be worth it to get several of those fish and enjoy how they act together.

Answer by  bigwig (654)

It is easier for fish to breathe if water is rushing past their gills. Darting around the tank forces the water past them more quickly, increasing the amount of oxygen they are taking in. Also, fish are on a constant quest for food. Many types of fish move around a lot; they probably aren't "hyper. "

Answer by  Wade (168)

Just like all animals fish need exercise. If you have a small tank they may have to do more "laps" to get their exercise.