Yes. Betta fish can get jealous. It’s typically caused by a change in environment. This can include new fish added to the tank, a change in water conditions, or competition for food and territory.
If you’ve been looking at keeping betta fish, the odds are pretty good you’ve heard that they can be jealous, territorial, and aggressive.
You’ve heard correctly!
It turns out that betta fish have earned their reputation for being “tiny tornadoes” inside of an aquarium. These fish – especially male fish – have a tendency to be jealous, get aggressive, and sometimes even fight to the death with other fish.
There’s a little bit of nuance to this, though, and that’s what we are going to spend the rest of this detailed guide digging into.
Do Betta Fish Get Jealous?
Betta fish have a long-standing reputation as some of the easiest fish to care for – when they are the only fish in the bowl, anyway.
Stick a second betta fish in the water, though, and you could be in for a surprise. Especially if that second betta dropped into the bowl is another male.
Female betta fish don’t have the super aggressive reputation that their male counterparts do, but the males have certainly earned this reputation – sometimes even with blood.
It isn’t at all unusual for betta fish to get jealous, to feel very protective and territorial, to fight over food, and just to “throw down” because they feel like it.
This is why it’s recommended that you only ever keep a single male betta fish in your tank (if any).
Why Do Betta Fish Get Jealous?
There are a lot of reasons that betta fish can get all twisted up, jealous, and confrontational and we run through many of the most common root causes of this behavior below.
New Fish Added to the Mix
Adding a new fish into an already established tank is something that has to be done very carefully and very deliberately.
It really doesn’t take all that much to “upset the apple cart”. Especially when you are dealing with a breed of fish like the betta that already has a tendency to want to get a little on the wild side with strangers.
The overwhelming majority of people that keep betta fish make sure that they only ever keep female fish in the same tank with one another, or they keep only a single male in with the ladies and then the rest of the fellas in separate tanks.
It isn’t super common for betta fish – even betta males – to go after other fish when they are added to the tank, though. This does happen from time to time (particularly with especially dominant males), but again if you keep the tank pretty much all ladies you’ll have a whole lot less to worry about.
Major Changes to Their Water
What we humans might perceive as small changes to the water that fish live in are often seen as catastrophic changes by the fish that live 24/7 in this environment.
It’s important to remember that the overwhelming majority of fish in the wild have a tremendous amount of water to thrive in. They usually have more than enough resources or will move to another stretch of water that can provide them what they need.
Even the largest fish tank is going to be considerably smaller than what most of these fish are naturally attuned to.
They are always going to be competing for resources and any change – whether that be water composition, water temperature changes, or the addition of new fish to the water – are going to be seen as major alterations to their life.
Don’t be surprised if you’re betta fish feel like any change (no matter how small) is enough to trigger the fight or flight mechanism.
Competition for Food and Shelter
Competition for critical resources – food and shelter (as well as mating partners) – will certainly spur on some amends feelings of jealousy by your betta fish.
This is why almost every fish expert out there recommends that you feed your fish at the same, that you follow the same feeding pattern, and that you do absolutely everything you can to make sure that there is a surplus of resources in the tank no matter what.
As soon as the idea of scarcity starts to creep in these fish are going to want to fight it out, get jealous over another fish that they perceive to have more than them, and that’s when your school of fish can be threatened by angry bettas.
You want to be sure that your tank has lots of structure for your bettas to make their own as well.
A new fish muscling in on territory that a betta has already established as their own will surely cause a fight. There’s going to be competition and jealousy for these core resources, which is why providing more than enough structure is a huge piece of the puzzle in keeping a happy tank.
A Lot of Attention Showered on One Specific Fish
You might not think that fish notice whether or not one of them is getting more attention from onlookers (or owners) than the rest of the “pack” – but you’d be wrong!
It is critically important that you try and make sure that all of your fish get equal amounts of attention, get equal opportunities to perform, and get equal chances to show themselves off.
As soon as one fish starts to feel like it is getting the bulk of the attention it’s going to pump up the performance.
Before you know it a single fish is moving through all of the main swimming positions, and that soon as that happens the rest of the tank is going to recognize what’s going on.
In no time at all you’ll have betta fish identifying the process, getting jealous, and then looking for ways to interrupt the “star of the show” – even if that means slamming into it and getting into physical confrontations.
Even if you do have a favorite in the tank it’s a good idea to try and shower all of your fish with attention. As soon as you start to make favorites you drive up the envy and jealousy in your bettas, and that’s going to cause problems almost instantly.