Are your tropical fish stressed?

Tropical fish are among the most low maintenance and popular of pets, with many people enjoying watching their beautiful, vibrant aquariums when they have relaxed after doing all of the hard work and maintenance!

While fishkeeping of cold-water and freshwater tropical fish is something that virtually anyone can achieve successfully with a little research and effort, there are several common mistakes that even conscientious, experienced fish keepers can make on occasion, all of which can lead to stress, and potentially, affect the health of both your individual fish themselves, and your tank as a whole.

In this article, we will look at some of the main indications of stress in tropical fish, and what can cause it. Read on to learn more.

What sort of things can lead to stress?

A huge range of different things and combinations of things can lead to stress in tropical fish, and one of the most common of these is overcrowding, or having too many fish in the tank. This can happen very easily, as the amount of space needed for each fish to really thrive is often overlooked, and the vast majority of home aquariums are overstocked to some extent. This can be a particular problem if you keep guppies, which tend to breed easily and prolifically, leading to many more fish than you had planned for inhabiting your tank over time!

Keeping the wrong combination of fish species together can also cause stress, as not all tropical fish will get on well together. Large fish and very small fish together will often lead to stress on the small fish as they struggle to avoid being eaten, while some popular and pretty aquarium fish such as angelfish tend to be rather bossy and aggressive, and can soon upset their tank mates.

Changes to the tank itself and what it in it can be stressful for fish too, even small things like performing a big water change if the tank was overdue for cleaning, or rearranging the aquarium décor. The water chemistry and parameters are also something that can fluctuate and change, which is a hidden cause of stress that the owner will not be aware of without water testing, but that will have an acute impact on the fish themselves.

Dirty water or a tank that is not cleaned out enough will lead to stress and upset in your fish, which can also occur if your tank’s filtration system is not able to keep up with the size of your tank or the number of fish within it.

Extremes of hot and cold from the thermostat and changes in the lighting patterns can all cause stress too, and so a thermostat and timers to regulate the temperature and light are all advisable. Your tank should not be too bright for your fish, and if it is near to a window, the sun can affect both the tank’s temperature and lighting levels at different times of the day too.

Fish need to be able to feel safe and secure, and so a range of small hiding places and cover plants are important, particularly for small fish that need to hide from larger predators.

Finally, just adding one new fish to an otherwise well balanced tank can cause stress and upset while all of your fish get used to each other too, so consider any new additions carefully.

How to identify stressed fish

Learning how to identify the signs of stress in tropical fish is important, as if you are not aware of a problem, you will not be able to fix it! Once you have ascertained that some or all of your fish are stressed, you can then go about finding out what is causing their stress, and make changes in order to keep them happier.

Stress can be present in just one fish, a group, or all of the inhabitants of your tank, and how it presents can vary considerably.

If your fish are lethargic and appear sluggish or reluctant to do much, they might be physically ill, or simply not thriving due to stress. Loss of appetite is another big indicator to look out for, which can once again be a sign of a health condition too.

Fish that are swimming oddly, are hyperactive or that are otherwise behaving in a different way to the norm could also be exhibiting signs of stress, but these indicators can also mean a range of other things too, such as the onset of the breeding season!

Poor water quality or not enough oxygen in the tank too can lead to a general listlessness and other symptoms in your fish, and so testing your water parameters regularly is important.

Over the long term, stress from any source can lead to physical changes in your fish, such as dull or flaking scales, loss or change of colour, and a generally unkempt, ragged appearance, which is particularly likely to occur if your fish is being bullied by other fish in the tank.

Keep an eye on the behaviour, activity and normal parameters of your fish, and act quickly to correct any problems when you spot them.