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How To Understand The Basics Of Fish Behaviour


Training and Behaviour



If you have pet fish, you may have not actually paid much attention to how your fish act and interact with each other. But chances are you will have at some point thought why is my fish doing this or acting a certain way. Although fish behaviours are often subtle and harder to read than bigger pets like cats and dogs. That being said, it can be valuable for fish owners to gain a basic understanding of some of the behaviours that fish commonly exhibit. This can be helpful to identify any issues that arise or simply to get an insight into what your fish is up to!

Why is my fish hanging out at the tanks surface?

There are multiple reasons for why your fish might be hanging around at the very top of the tank; they might, for instance, be on the lookout for something to eat, particularly if they head to the top when someone approaches the tank. But they also may hang out at the top if the tank water is too cold, this can cause them to seek the heat from your tanks lighting system. Although it is important to understand your fish's’ natural behaviours first as some fish do just swim and feed at the top of the tank

Why is my fish gulping air at the surface?

People If your fish are at the top of the tank and appear to be gulping for air or actually sucking air above the surface, this is a clear sign that there is a lack of oxygen in the tank. This can be caused by a lack of aeration from not having an air pump or filter in the tank or by poor water conditions.

Why does my fish come to the top of the tank at feeding time?

Fish are smarter than you think, just like us they have an internal body clock. Which means once you get into a routine your fish will come to recognise the approximate times that they are fed. This can mean that they start to congregate around top of the tank in anticipation!

Why is my fish hiding?

If you notice that your fish is spending a lot of time hiding or being chased by other fish this could be causing them to feel stressed. A fish may hide due to poor health, being housed with unsuitable tank mates or overcrowding.

Why do some fish pick on each other?

Some fish are generally more aggressive than others, and many of the larger, more attractive fish are not suitable for keeping with quieter or smaller sorts of fish. For example t angelfish is well known for eating anything small enough to fit in their mouth. So naturally they are unsuitable for living with small schooling fish like neon tetras. When stocking your fish tank, it is important to carefully consider the balance of the different types of fish you wish to keep, and cross-check them to ensure that they will all get on. You need to do your research as some sorts of fish like the male betta or siamese fighting fish are better living alone due to their naturally aggressive behaviour.

Why is my fish scratching against rocks?

Often when fish scratch themselves again rocks or hard surfaces it can be a warning sign that they have a parasite. Parasites normally only become an issue if your fish is stressed or in poor health. If you notice your pet scratching, or any irregularity on their body or fins. You should test your water for high ammonia and nitrite levels and contact your local store to find appropriate medication. If you think you are dealing with parasites it is a good idea to keep your aquarium lights, increase your aeration and slowly increase the temperature of your tank to around 29 degrees, as this helps to disrupt the parasite life cycle.

Why does my fish swim together with others?

Some fish evolved to swim in schools to better protect themselves from predators, improve their foraging and swim more efficiently. This is the same when it comes to pet fish. Many small fish like tetras, rasboras, danios and barbs are schooling fish. So it is important to make sure that you keep a group of at least six together in order to enable and allow for their natural behaviour, or they will become stressed and unhappy.

Why is my fish floating or struggling to swim sideways?

Swim bladder issues are a fairly common problem, especially in certain species of fish like goldfish. Fish suffering from swim bladder issues exhibit a variety of symptoms such as , floating upside down, sinking to the bottom of the tank, standing on their head, or struggling to maintain or swim in a normal upright position. Swim bladder problems can be caused by constipation or overfeeding, this can sometimes be fixed by feeding small bite sized pieces of blanched peas, that can help to clean the fishes digestive system. These issues can also be caused by poor water quality, so it is important to clean and test your tank water on a regular basis.

It is important to take note of what your fish is doing, as this can tell you a lot about how they think and how to meet their needs. It is good practice to always ensure that your tank is well planted with enough ornaments and plants to provide adequate hiding places. As well as to maintain consistently clean and healthy water parameters to avoid your fish from being susceptible to diseases or illnesses. You also need to keep an eye on your fish and how they interact with each other and take note of any fighting or aggressive behaviour as this may be due to unsuitable tank mates or overcrowding.

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Written by The Team

A team of specialists with backgrounds in animal nursing, animal care, and all things pet related.