As you pass by the fish tank, you may notice the fish behaving strangely or displaying abnormal physical characteristics. This is an indication that your fish has some type of disease and needs treatment. Learning how to recognize aquarium fish diseases and how to treat them will help you take good care of your fish and keep them healthy and stress-free.
Step
Part 1 of 2: Recognizing Aquarium Fish Diseases
Step 1. Observe the fish's breathing and movement
The way your fish breathe and move in the tank can tell you when your fish is sick. For example, fish don't swim as actively as they normally would. Some diseases can make fish unable to swim at all.
- You may also see fish rubbing against objects in the aquarium. This is called 'flashing' or 'glancing' and is often associated with external parasites.
- If you notice your fish moving their fins rapidly but not moving from their place, the fish may have gill disease. With gill disease, the fish may also just lie languidly at the bottom of the tank.
- Unusual breathing is also a common sign of aquarium fish disease.
Step 2. Observe the body of the fish
Diseases of aquarium fish can cause visible abnormalities in the fish's body. Parts to look out for include the bladder, fins, and eyelets.
- When a fish suffers from 'Pop-eye,' its eyes will become very large and look like they are about to pop out of their heads. This disease can be caused by bacteria or excess oxygen in the water.
- Fin rot is a disease that causes fish fins to turn dull and begin to erode. This disease can be deadly if the fins are eroded to the base – this will make the fish unable to move.
- A fish's bladder, which is located below the belly, can swell if the fish has bladder disease. Since a normally functioning bladder provides buoyancy, an inflated bladder will prevent fish from swimming or floating.
- If you look closely enough, you may see tiny parasites, such as mealybugs, attached to the fish's body. This parasite causes extreme irritation, prompting fish to flash or glaze to try to get rid of the parasite. Wounds will form due to this friction.
Step 3. Look for mucus in the fish
Mucus can be a sign of disease caused by bacteria or fungi. Ich, also known as white spot disease, is a disease caused by a fungus that produces mucus on the body and gills of fish. This disease is caused by a pathogen called Ichthyophthirius multifiliis. Mucus serves to ward off pathogens from the skin.
- Ich is one of the most common aquarium fish diseases and can be highly contagious.
- Other fungal diseases, such as mold of the body and mouth, can cause patches of mucus to appear on the fish's body.
- Columnar disease is a disease caused by bacteria that can produce a grayish white membrane on the fish body. You may also see gray or yellow patches on the fish's gills.
Part 2 of 2: Treating Aquarium Fish Diseases
Step 1. Check the water quality of the aquarium
Parasites, bacteria or fungi are common causes of aquarium fish disease. However, the presence of these pathogens in the aquarium does not necessarily mean that the fish will get sick. Often, the culprit behind aquarium fish disease is poor water quality.
- Checking the water quality is the first thing you should do if you notice your fish look unhealthy.
- Test kits are available that test the pH and hardness of water, nitrate, nitrite and ammonia.
- Poor water quality can increase the concentration of pathogens in the aquarium to levels that can make fish sick.
- Different fish species may have different water quality requirements. Consult your veterinarian or local pet store clerk for more specific guidelines on water quality.
Step 2. Recall any recent changes to the fish tank or routine
When you notice a fish is not feeling well, keep in mind any changes you may have made to the aquarium or to the fish's usual routine. Sometimes, these changes can cause stress which can make the fish more susceptible to disease.
- For example, ask yourself if you've added new fish to the aquarium, or replaced any of the water quality controllers.
- If you do add fish, keep in mind whether you quarantined any new fish before adding them to the tank. Sick new fish can expose other fish to disease.
- Also ask yourself if you recently changed your diet to fish.
- Also try to remember if you sprayed perfume or insect repellent near the fish tank. Chemicals from these materials may enter the fish tank and affect water quality.
Step 3. Quarantine the fish
Treating fish in separate aquariums is a good idea. To reduce stress on your fish from moving from one tank to another, keep the water conditions in the quarantine tank as close as possible to the conditions in the original tank. Also use plastic plants in the new aquarium to make the fish feel more comfortable.
- Use a water heater to make sure the water temperature doesn't drop below 24 degrees Celsius.
- Consider using a non-chemical filter, such as a sponge filter. Chemical filters can filter out any medications you add to the water. Also avoid using a filter with a strong power – this filter can cause turbulence in the water which can stress sick fish even more.
- Place an aeration stone in the aquarium to provide oxygen. Some medications can remove oxygen from the water, which can stress fish.
- Use the net to move fish from one aquarium to another.
- It is recommended to quarantine the fish for at least 10 days while you are treating it.
Step 4. Treat the fish
Fish food containing drugs and medications that are added directly to the water are the most common ways to treat sick aquarium fish. There are many antibiotic, antifungal, and antiparasitic medications available to treat sick aquarium fish. In addition, materials such as copper, formalin, and green malachite can be effective as drugs.
- You'll find a wide variety of commercial fish remedies at your local pet store. However, this drug may not have been tested for safety and efficiency.
- Consult a veterinarian or fishery expert for recommendations for well-known fish medicine.
- Carefully follow the instructions for using any medications recommended for your fish disease to ensure you are treating your fish properly and effectively.
Step 5. Return the fish to the aquarium
Once your fish have recovered from the disease, you can return them to their original tank. If there are several fish that need to be treated, disinfect the aquarium by adding 5% hydrochloric acid to the tank. Let the disinfectant sit in the water for a few days, then clean it and add a sponge filter.
- Products for cleaning quarantine aquariums are available at your local pet store.
- Talk to your local pet shop employee or your local water safety department about how to safely dispose of medicated water.
Tips
- The list of aquarium fish diseases is extensive. Consider investing in a comprehensive fish guide that provides detailed information on fish diseases and treatments.
- Skin sores are the most easily recognizable sign of aquarium fish disease.
- Maintaining good water quality and providing a low stress environment and good nutrition for fish may be all that is needed to keep fish healthy and free from disease.
- Water that is too cold (below 23.8 degrees Celsius) can contribute to fish disease.
- If you intend to add new fish to your tank, you will first need to quarantine them for 30 to 60 days. Be sure to maintain good water quality in the quarantine tank to keep the new fish healthy.
Warning
- Fish disease can progress to the point where treatment is no longer possible. Consult your veterinarian about the possibility of euthanizing your fish.
- High levels of nitrates, nitrites, and ammonia can be toxic to fish.
- Commercial drugs can do more harm than good. Check the composition label on the medicine container. Consult a veterinarian or fishery expert if you are unsure how to read and interpret composition labels.
