If you own or ever spend time with fish, you’ll know that sometimes they act in ways that can only be described as strange. All fish owners and enthusiasts will agree, often our aquatic friends engage in behavior that is odd, puzzling, entertaining, and sometimes even worrying.
Generally, strange fish behavior is just that: weird little fish behaving in weird little ways. Other times it can be a sign that something is wrong inside the tank, an indicator that your fish is not being sufficiently stimulated, or a tell-tale sign that they’re ready to breed. With all this in mind, let’s break down some strange fish behavior.
Why Do Fish Jump Out of Water?
One of the most alarming behaviors a fish can exhibit is jumping out of the water. There’s a reason why the phrase “like a fish out of water” is used to describe finding yourself in an environment that is unfamiliar and often uncomfortable. It is quite literally against its very nature and is cause for immediate concern.
A fish will jump out of water for several reasons. Some of these reasons include:
- Attempts to escape from predatory tankmates
- Territorial disputes
- Inadequate oxygen levels
- Poor water quality
To prevent this behavior, and ultimately keep your scaled buddy safe, you must maintain a well-balanced aquarium with good water quality and sufficient oxygenation. If you’re still worried about jumping, you should consider covering your aquarium with mesh or a lid.
Why do Fish Make a Bubblenest?
Have you ever spotted a floating mass of bubbles at the top of your tank and wondered what on earth it is? Well, wonder no more, because that’s a bubble nest. A bubble nest is exactly what it sounds like. It’s a nest made up of air bubbles. Plus, saliva and other secretions.
Typically triggered by hormones, bubble nest building is instinctive behavior exhibited in certain fish breeds (namely betta fish, some gouramis, electric eels, paradise fish, and snakeheads.) It’s most often male fish that construct these bubble nests to attract females for breeding and protect their eggs and fry when the time comes.
This bubble nest building is perfectly normal and quite fascinating to watch. What makes this behavior even more interesting is when it is exhibited by lone male bettas who build their bubble nests not to attract a mate but to communicate that they are incredibly content and healthy.
How Come Some Fish Constantly Hide?
Some fish have a natural tendency to hide inside plants, disappear into caves, or simply dwell at the bottom of their tanks. While there’s a chance that some fish simply can’t resist a good old game of hide and seek, there’s probably a better (though less fun) explanation.
So, why do fish hide? There are several reasons. It’s completely normal for nocturnal and shy fish species to hide or bottom-dwell. It’s in their nature. It’s important to provide these types of fish with adequate hiding spots such as caves, rocks, plants, and other decorations.
Fish species that are known to hide include:
- Clown pleco
- Zebra pleco
- Banjo catfish
Genetics aside, some fish will hide when they are first introduced to a tank and haven’t yet gotten used to their new surroundings. Likewise, it’s normal for fish to become much less visible when they are guarding eggs and fry. We also know that fish can feel emotion, and one of those emotions is stress – most of the time, this stress is the result of bullying by another breed.
However, it’s important to note that this behavior can also be observed in fish that are feeling stressed or sick. If your fish is usually very visible but has recently begun hiding, this could indicate an underlying health condition like ick, bloat, or bacterial infection.
Why Do Fish Flare?
Have you ever noticed a fish puff up its fins and gills, making it look bigger and stronger? If so, you’ve witnessed flaring in action. This strange behavior is observed in several fish breeds, including fire mouth and jewel cichlids and certain types of gourami, but is most associated with betta fish.
Betta fish are renowned for their stunning coloration and elaborate fin displays. They are also known for something else: flaring! Though a fantastic fish for first-time owners, betta fish are famous for flaring their fins out in dazzling displays of aggression. A betta fish will even flare at its own reflection in the aquarium glass.
This behavior, though strange to us humans, is completely normal in betta fish and is linked to their territorial instincts. Flaring in bettas is almost always due to aggression but can also be triggered by excitement. It’s important to note that prolonged flaring can cause fin damage and even stress, so do your best to minimize potential triggers in your tank.