Why Is My Molly Attacking Other Fish? (Important Precautions To Take)

Though mollies are popular fish for aquariums still most of the aquarium owners get worried when they see their molly chasing other molly or other fish in the tank. In this situation, a question arises whether mollies are aggressive.

In this write-up, we are going to discuss reasons why mollies chase each other and look aggressive.

Reasons For Molly Chasing Other Molly

One of the main reasons for which a molly fish chases another molly fish and looks aggressive can be linked with their behavior to seek attention as part of their mating ritual. For this reason, in an aquarium, you can see a male molly fighting with other male mollies or chasing a female molly. 

Moreover, male mollies also become territorial like other animals and in an aquarium, they fight with other male mollies to protect their interests from them.

You can control their aggressiveness by adding enough number of female mollies to the tank or by using a large tank for your aquarium to provide them enough room to swim in.

Are Mollies Aggressive By Nature?

Usually you can find male molly chasing a female in an aquarium. The purpose of this chase can be to mate. In this chase, the male molly will not harm the female molly as it is absolutely normal behavior. But they can chase other fish aggressively when they are breeding. But normally mollies are not aggressive by nature as mollies can occasionally be found scared. 

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You cannot witness such chases in your aquarium if all the mollies in it are female as they will not find a male molly to mate and reproduce more mollies. In this situation, you must be able to know when is the mating season for a molly.

The aggressive chasing of a female molly in the tank can be one of the signs that it is their mating season. Another sign of mating season for mollies is when male mollies try to attract the attention of a female molly to mate with her, by splitting up into groups.

Reasons To Fight With Other Male Mollies

You can witness a lot of fighting and aggression in your aquarium if you have many male mollies in it. You can avoid fights between several male mollies either by using an exceptionally large tank for your aquarium to provide every molly enough personal space or by keeping one male molly with three female mollies.

But if you cannot buy a large tank then male mollies will chase each other due to frustration as they cannot do anything else. Sometimes they fight with other male mollies while trying to protect their territory. So you can see mollies fighting with each other due to various reasons. It can be to attract the attention of a female molly or due to territorial issues between male mollies.

When male mollies fight with each other then one of them can be seriously injured or die as a result of the fight.

The chances of such consequences can be more when you are adding a new male molly in a tank of male mollies. To end this endless chase you are advised not to put one female molly with two male mollies in one tank.

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Should You Keep Mollies Separate?

It can be a good idea to keep mollies separate due to various reasons.

You can retain the offspring of recently hatched fish without a yolk-sac by separating her from other mollies when she was pregnant. Otherwise if she gives birth in the presence of other mollies then they will eat them all.

If you have too many mollies in your tank then by separating some of them in other tanks you can considerably reduce their aggressive behavior. Mollies feel threatened when they are crowded. This threat makes them more aggressive even if they are usually peaceful by nature. You can also talk to the owner of fish store to know how many mollies are perfect for the aquarium tank you have.

You must have an aquarium with 30 gallon capacity to keep four large size mollies in it so that they can live peacefully. However a tank with20gallon capacity can be enough for you if you want to keep 3 or 4 small mollies in it.

Precautions To Take For Mollies

To prevent injuries and deaths of mollies the owners of aquariums should take a few careful steps. They can prevent untimely death of their mollies in the tank by taking some steps to stop their mollies to chase others. After a thorough research some steps are suggested here under in this regard.

  • You should know how many mollies and other fish you have in your tank. You should keep two female mollies with one male molly so that he does not get frustrated in the absence of many females around him.
  • Always use a bigger tan while adding mollies to it as every molly needs enough space to move on as well as relax in it. For two molly fish you must use a tank with at least 15 gallons capacity.
  • A long tank can be good for matting instead of tall one.
  • At the time of labor always put female molly in a separate tank to assure the safety of the newborn babies without any problem.
  • To allow the fry to grow up you must use a tank of 50-gallon capacity and feed then with newly hatched brine shrimps and micro-worms.
  • Provide good quality food to molly fish as it is an omnivorous creature which can eat all types of food including frozen, artificial and live food. However, algae and vegetables can be the best food for them. You should not keep them hungry for long as they can get aggressive when hungry.
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So, if your Molly attacks other fish then you must know the reason behind such behavior. It can be due to their mating period or due to lack of enough female mollies according to the number of male mollies in the tank.

You should take a few careful steps to reduce their level of aggression. You can increase the size of your tank to provide your mollies enough space to relax and move on peacefully.

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