A Detailed Guide On How to Stop Guppy Bullying

Guppies are hardy creatures, so there is no doubt that many aquarists enjoy growing them in their aquarium.

However, it is very difficult to predict the behavior of guppies. For example, you can notice that guppies consistently bully and chase their tank mates.

We bet many people are in a similar situation and wonder, “How to stop guppy bullying?” If it is also your case, this article will be helpful.

Besides, we also share several tips to help stop your guppies from bullying other fish and why guppies bully each other. Scroll down to read the details now!

How To Stop Guppy Bullying?

Isolate Aggressive Guppies

Sometimes, isolating aggressive guppies is the only way. Some individuals are naturally more aggressive than others, and you have no choice but to separate them from the main tank.

Maintain a Large Group of Guppies

The guppies feature a schooling behavior which is a defensive mechanism they will use when sensing a threat.

Also, this social behavior will minimize aggression and promote more positive social interactions. We recommend keeping six guppies in your tank.

Offer Hiding Spaces

In natural environments, guppies have various hiding places where they can hide when threatened. So your tank should provide them with the same thing.

Add Live Plants

Guppies tend to feel more comfortable in the plant-rich environment when facing many stressors such as bullying, harassment, and perceived threats.

Various plants can be added to your aquarium. You should also remember that some plants feature specific attributes.

For example, Guppy Grass can reduce nitrates, ammonia, and heavy metals in fish tanks, delivering guppies with a  more stable and cleaner environment.

Java Moss may promote the growth of Infusoria, which various fish fry will eat during their first weeks.

Why Do Your Guppies Bully Each Other?

Lack Of Food

feeding guppies

If your fish are starving, the larger ones may bully the smaller one

When your guppies are hungry, the strongest will bully the weaker ones into getting more rations.

If this situation persists, the aggressive ones will become more violent towards others who compete with them over food.

If it is the case in your aquarium, your fish will calm down after the daily meal.

You may see this behavior if you have skipped meals or the portions are insufficient to meet the tank’s needs.

Size Differences

Sometimes, the aggressive behavior of this fish stems from size differences. We’ve seen massive guppies attack smaller ones if they had a chance.

This bullying type is most dangerous in a tank with a small community of guppies as one fish or two might become the target of all the tank’s hostility.

Mating Competition

Guppy females can mate at any time, resulting in much male bullying and harassment.

So guppy males may harass females and bully other males at the same time. The males get pushy and try to mate even if the guppy females are not interested.

The situation may degenerate fast, resulting in guppy males hurting others. They don’t kill each other, yet larger males may hurt smaller ones by nipping their fins.

Although guppy females typically do not get physical damage, they will experience stress because of the guppy males’ persistence.

Lack Of Swimming Space

crowded guppy tank

Your guppies can be aggressive if your tank is overcrowded

The small tank with too many species can lead to a problem of overcrowding that may stress guppies.

The males might be territorial, especially when competing for females, increasing their aggression. Also, guppies might bully or attack smaller ones.

These problems can be minimized for larger aquariums with various live plants in decorations.

In this case, guppies will get various hiding places, breaking the vision between aggressors and victims and minimizing aggression.

Ideally, you should make sure each guppy gets 2 gallons of water.

Poor Conditions

A poorly maintained tank may encourage hostility in your guppies.

Not ideal temperatures, improper pH, and the accumulation of toxins like ammonia may cause stress in fish.

So if your guppies are suddenly acting abnormal, you need to test your tank water to ensure that all the parameters are reasonable.

Here are the ideal water parameters for your guppy aquarium:

  • Water temperature: Between 72 and 82℉.
  • Water hardness: From 8 to 12.
  • Water pH: From 6.8 to 7.8.
  • Ammonia, nitrites, and nitrates should be approximately zero.


Can I Keep an All-Female Guppies Tank?

Although keeping an all-female guppies aquarium is feasible, we do not recommend it. While an all-female guppy tank can work, it often leads to bullying and aggression.

But if you decide to follow this path, providing various hiding areas and keeping track of your fish is essential.

Why Do My Female Guppies Fight?

Aggressive behavior doesn’t just happen in males. Female guppies can also become aggressive under certain circumstances, such as:

  • Territorial behavior
  • Pregnancy
  • Enforcing the pecking order
  • Improper water conditions

Can I Keep Two Female Guppies?

Yes, two females can live together in a tank.

But we recommend keeping more than two guppies together as they are social creatures that work well in a group of their kind.

Can I Keep Two Male Guppies?

Yes, you can have two male guppies together, though they may chase each other to fight over a female or assert dominance.

Can Guppies Kill Each Other?

Yes, it is possible. Although guppies will not actively kill each other, it can result from constant bullying.

Guppies may nip at the fins of others, leading to injury and leaving them vulnerable to infection.

Bullied guppies can experience prolonged stress, making them vulnerable to many health problems, and some may become contagious.

The Bottom line

Bullying is one of the serious problems that can cause your fish to die. If you think that your guppies are being bullied, you must do something to stop it.

We have mentioned some ways to stop guppy bullying. You should try different tactics until you get the one that works best for your fish.

Thank you for your interest in the article!