Guppies are social, active fish, and a certain amount of chasing is normal. Males display, compete, and follow females. Fish also jostle during feeding. The difference between “normal guppy energy” and harmful bullying is simple: can every fish rest, eat, and move freely? If one fish is constantly cornered, hiding, or losing fins, you have a problem that will worsen over time.
Normal chasing
- short bursts around feeding time
- brief male displays and posturing
- males following females, but females still escape and rest
Problem chasing (bullying)
- one fish is targeted repeatedly all day
- clamped fins, hiding, or refusing food
- ragged fins from persistent nipping
- stress signs (fast breathing, dull colour)
Why it happens
Bullying usually increases when tanks are overcrowded, cover is poor, or sex ratios are unbalanced. It can also happen when a particularly dominant fish is present.
How to calm the tank
- Add cover: plants and decor break line-of-sight.
- Review ratios: too many males often means constant pressure.
- Feed smarter: small frequent feeds reduce competitive aggression.
- Remove the bully: sometimes one fish drives most problems.
A calm tank is not a “boring tank.” It’s a tank where fish feel safe. When bullying is reduced, guppies show better fins, brighter colour, and more consistent behaviour.
