If your fish is staying in one spot without moving, then the primary reason for this could be stress. But stress does not just form in one day, there must be several factors that lead to stress in fish. It is always advisable to build conditions in your fish tank that keeps them healthy and happy and prevent condition that builds stress.
There are many factors that decide if your fish will go in stress or be happy most of the times. Let’s have a look at some of these one by one.
Table of Contents
Water quality
Out of the most factors, water quality must be given top most priority. Water for fish, is like air for humans. If water is bad or unhygienic then fish will not survive. Bad water does not always mean visibly bad, it can have dissolved toxic gases that can kill fish as well. If your fish tank water is crystal clear it does not mean it is healthy.
A water filtration system with a combination of mechanical and biological filter works best, when it comes to maintaining water quality. Also with filtration, changing 20-25% water using a strict schedule does help in maintaining it’s quality.
The best way to ensure that the water is safe is to test it regularly using a “water testing kit” (paidlink) and keeping an eye on levels of dissolved toxic gases. The most prominent numbers to look out for will be ammonia, nitrites and nitrates as these are highly harmful for fish health.
(paidlink)
Water temperature
If yours is a tropical fish tank then keeping the water temperature within the advisable range is absolutely necessary. If your water heater is of low capacity than the required numbers it will not heat the tank water thoroughly? In such cases pockets of temperature will form and some fish will try to sit in positions where they find it comfortable without moving much from those spots.
From outside you’ll see they are staying at one position all the time and the reason could be they are finding the perfect temperature comfort zone. To avoid this issue check if your water heater is sufficient enough to heat the entire water capacity. You can also check water temperature at different spots of the tank and fairly assume if your heater capacity is sufficient or not.
Some tanks have a power head or a wave maker that circulates water within the tank so that surface of the tank gets agitated for easy exchange of beneficial gases. In such cases you’ll see the heated water at one end gets rolled over to the other end creating even spots. But if you don’t have any such equipment installed then it’s better to have your water temperature tested at different spots to avoid pockets of beneficial temperature.
Tank mates
Tank mates play a major role in fish health. In fish community bullying is a major issue and stronger fish tend to attack and sometimes even kill smaller and newly introduced fish. To avoid such accidents you must study “fish compatibility” before buying new fish pairs.
The new fish must safely live with the original species and are good in social interactions. If not, there will be fights. To avoid such fights fish will tend to occupy a corner of the tank by staying at one place all the time because of stress. Since tank is a confined area they can’t move away from such tragic conditions but to surrender themselves to stress and eventually die.
Diseases
Just like humans when fish get ill they are more likely to stay at one place. Disease deprives them of energy for moving and living happy life. They will avoid eating food, interact with other tank mates and try to hide behind decorations or plants.
It’s always better to prevent disease than to cure them once you see them. If you find that a fish has abnormal behavior or spots on it’s body then he may be sick because of some disease. In such case its always better to move him to a quarantine tank and treat him there.
Diseases if not treated lead to stress and can even kill them. Never treat your sick fish in the same tank with other normal and healthy fish swimming around. This is because medications added to the tank can have adverse effect in water chemistry and this can be harmful for other healthy fish. Some medications even have a side effect of decreasing dissolved oxygen levels. If this happens you’ll see your fish gasping for air at the top surface of the water.
Sleeping
Fish tend to sleep when there is dark outside. In natural world the sunlight is the main source of natural light, but in a tank the depth of the water not being too much as compared to natural waters, the tank is most of the times being lit from outside or room lights.
If you have artificial lights setup above aquarium, then its better to turn them off to replicate natural conditions of light and dark. Fish tend to sleep with their eyes open and by staying at one spot. This condition should not be confused with other conditions when fish stay at one place even during bright daylight conditions.
Fish tank environment
There are many things that are responsible for creating a healthy environment for a fish. If you newly introduced a fish in your tank and you find that he is staying at one spot then wait for some time to get him adjusted to the water quality, temperature, eating habits and tank mates.
As he gains confidence he’ll start moving around and exploring things on his own. Fish that are bought from pet store are normally under great stress because of constant human movement around the tank in the pet stores. Many times kids who visit the tank tap on the tank glass and even such simple act can produce stress.
When that fish moves to your new tank he will take some time to explore things and get adjusted to new environment.
Amount of Dissolved oxygen
When your tank has less amount of dissolved oxygen, fish will gasp for air at the top of the tank. If your fish is staying at one spot near water surface then probably he’s getting good amount of oxygen which he can’t get at the bottom of the tank. Fish breathe oxygen that gets dissolved in the tank water. This exchange of gases happens at the top of the water surface.
To encourage this gas exchange many tanks have air pumps installed out of the tank. This pump pushed fresh air in the tank water through a tube. The air escapes through an air stone and moves upwards creating a spectacular air bubble because of the air stone. When these air bubbles reach the water surface it get agitated because it’s area gets increase and this is where oxygen gets mixed in the fish tank water.
If enough area is not getting agitated then the tank will have less amount of oxygen entering the water through surface exchange and fish will gasp for air at the top of the tank or stay at one spot so that they get enough oxygen right at the top surface.
To avoid such situations check the compatibility of your air pump and if it is sufficient to agitate enough water area for easy exchange of beneficial gases. Many tanks make use of power heads or wave makers to agitate water surface for oxygen exchange and this works best for larger tanks. Some fish tank owners avoid use of air pumps because it produces a humming sound in the room where the tank is placed.
Pregnancy
If a female fish is pregnant then it will probably stay at one place behind decorations or plants to find a safe spot to lay eggs and protect herself from attacks. In such cases learn to identify a pregnant fish and shift her to a quarantine tank to avoid accidents.
Apart from staying in one spot there are many fish behaviors that fish display when they are in stress. All kind of stress lead to diseases and if not treated can cause death as well.
It is always better to first keep fish in a quarantine tank when you buy them from a pet store and observe behavior in this hospital tank for at least 15 days. Many times fish that are bought from pet store are already under stress and need a breathing space before you add them in a community tank.
Fish behavior that you must observe could be
1) Erratic swimming patterns – This could be staying in one place all the time, rubbing body against glass walls, decorating items, swimming back and forth.
2) Losing appetite – when fish lose appetite the first thing they will do is stop eating or eat very less. When this happens most of the food gets settled at the bottom of the tank beneath the substrate and starts decaying producing ammonia gas. This can be extremely dangerous for fish
3) Hiding – Fish that are under stress find safe spots in the tank behind plants or decorating to protect themselves from attacks.
4) Change in body color – Healthy fish are always bright in color and fish sunder stress show a pale color and some species even produce black spots on their skin.
5) Gasping for air – Fish under stress find it extremely difficult to breath normally and gasp for air at the top surface of the tank water.
To prevent all these it is necessary that you learn to observe fish behavior closely and identify stress when it starts to build in fish. Careful planning and maintenance will prevent such things happening in your tank and fish will feel safe and happy with the company of other fish around. The bottom line is to provide the same conditions like the natural world where these fish are supposed to live happily.