Best Medications for Treating Aquarium Fish Diseases

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When a pet dog or cat gets sick, you take them to the veterinarian. What do you do when your fish get sick? Aquarium fish diseases are more common than you might imagine, especially in tanks where new fish or other aquarium habitants have recently been added. Not only are aquarium fish diseases fairly common, but they can be tricky to treat because anything you add to the tank water in terms of treatment can change the water chemistry.

To help you pick the best medications to treat aquarium fish disease, we’ve assembled a list. Keep reading to learn more about common aquarium fish diseases and what products are best to treat them.

Related: Best Fish Food for Aquarium Fish

The first step in treating aquarium fish disease is identifying the problem. Take what you’ve learned above and do your own research to figure out what disease is affecting your fish. From there, you can consider some of our top picks for the best aquarium fish medications reviewed below:

  1. API Stress Coat: This medication is technically a water conditioner, but it provides other benefits as well. In addition to removing harmful chemicals like chlorine from tap water, it also replaces the fish’s protective coating that may have been damaged by stress or disease. It comes in a wide range of sizes so you can always keep it on hand.

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2. API General Cure Powder Medication: Designed to treat a wide variety of parasitic infections, this medication comes in the form of a powder for easy administration. This powder can be used in freshwater and saltwater tanks to eliminate problems like gill flukes, hole in the head, and swollen abdomen, among others.

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3. API Super Ick Cure: Choose from several sizes of this powerful ick cure that quickly kills the parasite within 24 hours of the first dose. It is for use in both freshwater and saltwater tanks and also adds a slime coat for protection against future disease.

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4. Kordon Methylene Blue: This aquarium fish medication comes in a 4-ounce or 8-ounce bottle and is designed to treat a variety of fungal infections. It can be used in freshwater and saltwater tanks as an alternative to malachite green. It is highly effective and affordable.

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5. Seachem ParaGuard: This easy-to-use parasite control contains no formaldehyde or methanol, making it both fish and filter safe. It is also formulated for use without altering the pH levels of your aquarium. This means that it is a safer option than the highly toxic formalin-based medications for those who aren’t comfortable with their use.

It is recommended to for the treatment of a variety of ectoparasites and external fungal/bacterial/viral conditions in exotic fish including ich (white spot), velvet, fin rot and flukes. It is safe for use in freshwater tanks and marine environments; however, it should NOT be used when treating an aquarium that includes invertebrates, crustaceans, corals, or elasmobranchs (such as sharks, rays or skates).

If you are looking to treat a receiving tank for new fish or a hospital tank, this is a great option. It is also recommended for use any time that new fish are introduced to your community freshwater tank.

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6. Seachem Cupramine Copper: Intense parasite infections sometimes require a stronger medication and this copper treatment is a great option. Rated for both freshwater and marine use, this medication is effective against a variety of external parasites. It is less toxic to fish than other copper medications and won’t affect filtration.

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7. Fritz Aquatics Mardel Copper Safe Treats: If you’re worried about a copper treatment affecting your filter or discoloring your tank water, try this treatment. This medication is safe for freshwater and saltwater tanks and it treats everything from ick to flukes and anchor worms.

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8. Hikari Prazipro for Aquarium: This aquarium fish medication contains <5% praziquantel by weight and is designed to treat conditions caused by tapeworms, flatworms, and flukes. It is extremely safe and highly effective, not to mention affordable.

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9. AquaCura Prazi-Cura Fish Medicine: AquaCura Fish medicine contains genuine praziquantel and has no additional fillers or medicines. It is a great choice to deal with fish with flukes like liver flukes, gill flukes, internal parasites, and worms.  The praziquantel is mild to your fish while offering maximum impact on the worms infecting your fish and tank. To use just add 1 gram of Prazi-Cura quick acting powder to every 100 gallons of your tank water.  The formula will paralyze and kill the worms while helping your fish shed them safely. This is excellent choice for goldfish, koi, and ornamental fish.  

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10. API Melafix Bacterial Infection Remedy: Whether you are currently working to combat a bacterial infection in your freshwater tank, or looking for a preventative when introducing new fish, API Melafix is a great option. While this all-natural antibacterial remedy isn’t a ‘fix-all’ for fish problems, it does work for a wide variety of different situations. It contains a natural, botanical tea tree extract and Melaleuca, which both help to heal bacterial infections while also repairing open wounds, damaged fins, and ulcers.

Specific conditions that this remedy is designed to target include open wounds and abrasions, fin and tail rot, eye cloud, pop eye, body slime, and mouth fungus. 

To maximize the benefits of this remedy, add it to your water daily for a week to treat existing infections. It can also be added for 3 days when new fish are being introduced to prevent unnecessary infections and reduce the risk of disease outbreak in your freshwater tank or aquarium.

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11. API Aquarium Salt: Though technically not a medication, aquarium salt is used to treat a wide variety of aquarium fish diseases. It promotes general fish health as well as gill function and may speed recovery from disease.

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Always use caution when treating your aquarium for anything, including disease. Adding chemicals or medications to your tank can change the water chemistry which might have a negative impact on your fish more significant than the disease itself.

Aquarium fish can be affected by a wide range of different diseases, some of which are easier to spot than others. In many cases, the first sign of illness is a change in behavior. If your fish stop eating as much as they usually do or if they are less active than usual, you may want to take a closer look to see if you spot signs of disease.

Here are some of the most common aquarium fish diseases to look for:

  • Body Flukes – Caused by undesirable tank conditions, body flukes are tiny flatworms that eat away at the gills, fins, and skin of your fish.
  • Anchor Worms – Typically introduced to the tank by new fish, anchor worms are actually tiny crustaceans that burrow into the skin and enter the muscles.
  • Dropsy – Typically caused by a bacterial kidney infection, dropsy occurs when the fish becomes bloated and has trouble swimming properly.
  • Ick – Easily one of the most contagious aquarium fish diseases, ich is caused by tiny parasites that look like tiny white spots all over the skin.
  • Fungal Infection – Fish can be affected by fungus on many parts of the body and it often looks like a white cottony growth. Fish with fungal infections are more susceptible to other diseases.
  • Gill Flukes – These are flatworms that measure about 1mm long and typically affect the gills. Fish kept in poor water quality or overcrowded tanks are more likely to get this disease.
  • Fin Rot – Typically caused by a bacterial infection, fin rot can also affect your fish’s tail or mouth. You may notice fading color and fraying of the fins and tail.
  • Lice – You may not think of lice as a problem for aquatic animals, but they can affect fish. You’ll usually see restless behavior and see tiny pale dots crawling on your fish.

Now that you have a better understanding of what to look for in an aquarium fish medications, it’s time to start shopping! Keep reading to see our top picks.

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