How to Cure Fungus on Aquarium Fish
If your fish has a white- or gray-colored growth on its mouth or body (often with a fluffy texture like cotton), it could have a fungal infection. Stressful or poor water quality can often cause fungal outbreaks. Secondary diseases can quickly develop so it is important to get the problem addressed immediately. We will be discussing both the treatment options and ways to prevent fungus from returning in this article.
When you see any symptoms of illness, the first thing we always recommend is a thorough cleaning of the aquarium. Before beginning treatment, we want the environment to be healthy and free of stress. Scrub the glass so that you can easily see the fish’s condition, clean out the detritus in your filter, and use a siphon to vacuum the substrate and change the water. For a step by step guide on cleaning an aquarium, see this article.
Fungus is often preventable, so the next step is to find the cause of the infection. There’s no point in treating the fish if we don’t stop the source of the problem because then the fungus may come back again in full force.
What Causes Fungus in Fish?
Fungal infections are often caused by poor water conditions. Many betta fish are affected by this disease. This is because their water containers have no heaters and filters. Bettas prefer temperatures between 78 and 80 degrees F. This means that they require a heater in rooms below this temperature. Also, it helps to house them in an aquarium that holds at least 5 gallons or more to prevent their waste from quickly fouling the water. To remove harmful waste compounds, it is important to do regular water changes and add live plants (especially floating) to your fish tank.
Nutrient deficiencies can be another reason why fish get fungus. To be healthy, fish, just like humans, require a balanced diet. Fishing from the same jar of flakes every day is like giving a person only hamburgers every single day. Sure, they can survive, but their bodies probably aren’t in tip top condition. Therefore, make sure to a) provide a wide assortment of foods so that they get all their essential nutrients and b) give them fresh, high-quality foods. Yes, the expiration date on the container may say the food is good for another three years, but every time you open the container, more air and moisture get inside, causing the food to become stale in a matter of months. Splitting the fish into smaller bags can help preserve freshness. Avoid using your fingers to lift food from the container. This can cause mold and other diseases.
Feed your fish a variety of high-quality foods to make sure they get all the vital nutrients to boost their immune systems.
Many livebearers are fond of fancy guppies, mollies and other exotic fish. They often contract fungal infections as soon as they return home from the pet store. This article will explain why aquarium fish that are not as hardy are becoming more common. Therefore, it’s cheaper to raise them in a mix of fresh water and salt water. When your guppies have been raised in brackish water for their entire lives and then suddenly get dropped into a purely freshwater environment, they’re often left in a very weakened state that makes them susceptible to foreign pathogens like fungus spores.
The bottom line is to try to eliminate stress as much as possible. Reduce bullying and aggression in African cichlids. Keep the gravel clean for bottom dwellers and the water quality for sensitive species high. Avoid keeping shy fish close to bright lights, TVs and other high traffic areas. Consider moving older animals that have weaker immune systems into a “retirement tank” with less activity and competition.
How do you get rid of fungus on fish?
If your fish’s mouth shows signs of fungus or rot, we recommend using Maracyn. Columnaris is a type of bacterial infection that looks like a cottony growth or grayish-white areas around the mouth. This should be treated with antibiotics. Clean the aquarium thoroughly and get rid of any chemical filtration such as activated carbon or Purigen. Follow the manufacturer’s instructions by using 1 packet for every 10 gallons of water, and then repeat every 24 hours for five days. Make sure to complete the full 5-day treatment of medication, even if the symptoms seem to disappear, because the infection could still be present in the fish’s system.
Maracyn or Ich-X can be combined if the fungus is found elsewhere on the fish’s skin. Ich-X is a combination of formaldehyde and methanol that are effective against fungal infections. Clean the aquarium thoroughly and get rid of any chemical filtration before you start treatment. For minor fungal infections, you can use 1 packet Maracyn and 1 teaspoon of Ich-X for 10 gallons each. Allow it to soak for a full week. Once the symptoms have disappeared, you can repeat this process. If the symptoms still remain or if the fungal infection is severe to begin with, use 1 packet of Maracyn and 1 tsp of Ich-X per 10 gallons of water, and repeat the dose every 24 hours for 5 days in a row.
Salt is an excellent way to treat mouth and body fungus if you don’t own a planted aquarium. Any form of salt that contains sodium chloride (NaCl), can be used. However, for this article we will use rock salt or aquarium salt.
Salt has been used for medicinal purposes for many years. We’ve found that most tetras can tolerate salt. However, other fish like anchor catfish are very sensitive to it and should never be exposed to salt. To make sure your fish can endure the salt treatment, start with a low concentration of 1 tablespoon of salt per 3 gallons of water. If the fish is healed after one week, gradually remove the salt via a series of weekly 30% water changes. If the fungus is still active, you’ll need to increase the salt concentration. Continue reading for more information on salt dosing. You can also use salt in conjunction with Ich-X to pack a powerful one-two punch against the fungus.
Will Other Fungal Medications Work?
Our experience shows that herbal remedies do not work well against fungal infections. Fish that are afflicted by the disease will need stronger medications to protect their lives. After many years of running a fish store and helping hundreds of customers, Maracyn, Ich-X, and salt are the treatments we have found that work best against fish fungus.
Although fungal spores will always be present in our aquariums eventually, they can usually be prevented from becoming serious infections. You can boost your fish’s health by providing them with the proper nutrients and stress-free environment.
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