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Do Glofish Eat Each Other? Read This First!

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Glofish are absolutely beautiful fish. It is no wonder that so many people want to add them to their tanks. But, have you noticed that your Glofish are starting to dwindle in numbers? Wondering if they are eating each other? Read on. We have the answers.

So, do Glofish eat each other? Well, it depends on what type of Glofish you have. Some are more prone to aggression than other Glofish. For example, a Glofish Betta is more likely to attack other Betta than a Glofish Tetra would do. It is important that you understand what the needs of the fish species are. 

If you read on, we are going to go into depth on what could cause Glofish to eat one another. We also want to share a bit of information on how you can prevent it from happening.

Do Glofish eat each other?

It is highly dependent on the species of Glofish that you have.

As you may well know, Glofish are pretty much laboratory-made fish. You won’t find them out there in the wild. Well, you shouldn’t do. We know that there are some people that have attempted to introduce Glofish into the wild. The Glofish never fair well like that.

Glofish have been developed by tinkering with the genes of a variety of fish species. This has helped to give the Glofish those attractive colors. However, you need to remember that other than a bit of genetic modification for the colors, the species of the fish hasn’t changed. A Glofish Betta fish is exactly the same as a normal Betta fish, for instance.

This means that you need to pay attention to the species of Glofish that you have. For example, if you do have a Glofish Betta, then it is probably going to attack, and perhaps eat, other Betta in the tank. However, if you had a Tetra or Danios, it probably won’t.

What can cause Glofish to attack one another?

At the time of writing, there are seven different Glofish species. This does make it difficult for us to give you general advice on how to prevent them from killing one another. This is why we are going to give a brief overview.

Do bear in mind that 99% of the time, if Glofish are killing one another, it is because there is something that is causing them to be uncomfortable in the tank. If you can uncover what that is, then the problem can be dealt with rather easily.

The school size is too small or too large

If you have a Betta fish, they tend to thrive on their own. Add another Betta fish into the mix, and they are going to attack one another. It is very rare that it doesn’t happen.

If you have a Glofish Tetra, then you will need a minimum of five Tetra in the tank. This is because they are schooling fish. If you have anything under 5, then they start to get aggressive as they don’t feel that they have been properly ‘protected’. 

Every species of Glofish will have an ideal fish number and tank size. Do your research here. In most cases of Glofish eating one another, this is going to be the problem.

There isn’t enough food

You need to ensure that you have enough food for your fish.

All of the fish in your tank needs to be able to reach the food. For example, you have some fish that feed from the top of the tank. If you are not dropping enough food in, then they may eat it all. That food may not reach the bottom-dwelling fish.

If fish seem to be scavenging around the bottom of the tank, then there is a strong chance that they are scavenging for food. You may also notice that they are less active, or try and feed closer to the top of the tank than normal. 

There are predators in the tank

If you have smaller Glofish e.g. Tetras or Danios, then they are prone to getting a bit uncomfortable if there are predatory fish in the tank. These predators may not even eat the fish, but they may chase them around or bully them.

It is important that you choose fish that live well with one another.

Remember, if you do have predators in the tank, it could be those that are killing off the Glofish. This is because studies have shown that Glofish are much more appealing to predators than the typical fish. This is all down to their unique coloring. This is why Glofish would never thrive in the wild.

You have an uneven balance of males and females

This mostly applies to schooling fish such as Tetras. We would never recommend that you put Glofish Betta males and females together unless you are actually trying to breed them.

If you have an uneven number of males and females in a tank, then the males may try to kill off other males so they can get all of the female’s attention. 

The water temperature or composition is ‘off’

All fish have an ideal temperature and water quality. If you do not meet their needs, then they will end up hurting one another.

Again, it is important that you do your research into the specific type of Glofish that you have. This way you will be able to meet their needs perfectly.

One of the fish is sick 

Many fish are known to kill off sick fish. If only one fish was eaten, chances are that fish was sick. There isn’t much that you can do about this other than keeping an eye on the fish and spotting when they are ill. That is easier said than done.

Related questions

Can all Glofish species live with one another?

No. Each Glofish species will have its own requirements when it comes to water conditions. Make sure you do your research into each species to know whether they will be compatible with one another. If they aren’t, they may start feasting on each other.

Should you separate Glofish if they are eating one another?

Ideally, you would try and work out what is causing the problem in the first place. In most cases, there is an issue with the tank. It is better to deal with the issue than separate fish into separate tanks. If fish are removed from a tank, it could cause a great deal of stress. This can result in death.

See Also:
How to Acclimate Clownfish? Read This First!
How Often Do Jack Dempseys Breed?
How Many Cichlids in a 36 Gallon Tank?
How Much Bio Media is Needed Per Gallon in an Aquarium?