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How to Use Melafix & Does It Work?

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By Lindsey Stanton


Unlike humans, fish cannot tell you when they are sick and they definitely cannot go seek treatment on their own. It is up to you to notice the signs of illness and to react as fast as possible to prevent any casualties.

There are a lot of bacteria in aquarium water and on fish. Sometimes fish get sick and there just is nothing you can do about it. However, Melafix is a great solution for a variety of bacterial problems.

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What Is Melafix?

Melafix is an all-natural treatment for fish intended to protect against and treat a variety of bacterial infections that fish may suffer from. We do like the fact that this is an all-natural treatment for bacterial problems in fish.

Not being full of chemicals is something that both we and our fish greatly appreciate. You can use Melafix as a precautionary treatment for new fish in your aquarium. New fish often come loaded with bacteria, which can negatively affect them and the other fish in your tank.

A closeup shot of sick betta fish in aquarium tank
Image Credit: Wirestock Creators, Shutterstock

Using Melafix in your aquarium when adding new fish into the mix can go a long way in reducing the chances of your fish suffering from some kind of bacterial infection. Melafix can also be used to treat scratches, abrasions, and other wounds.

The wounds heal faster and there is a decreased chance of bacteria infecting your fish. Melafix is also shown to help re-grow tails and fins that have been damaged due to physical damage or bacterial infections.

If you suspect your fish is sick and want to ensure you provide the right treatment, we recommend that you check out our best-selling and comprehensive book The Truth About Goldfish on Amazon today.

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It has entire chapters dedicated to in-depth diagnoses, treatment options, a treatment index, and a list of everything in our fishkeeping medicine cabinet, natural and commercial (and more!)

Melafix is a good option to go with because it can be used for both saltwater and freshwater fish. There is also the fact that this medicine will not cause the water to go cloudy. At the same time, it is perfectly safe to use with other plants and fish in the tank, plus it won’t change the pH level or adversely affect the water filter. It’s probably one of the better options to go with for a variety of bacterial infections in fish.

What Is Melafix Used to Treat?

As we said before, Melafix can be used as a precautionary tool to stop bacterial outbreaks from occurring in new tanks or old tanks when new fish are being added. It helps cuts and sores to heal faster, plus it can help re-grow damaged tails and fins quite effectively.

In terms of bacterial infections, Melafix can be used to treat three main things, these being eye cloud, tail rot, and mouth fungus.

Eye Cloud

The first thing that Melafix can be used for is something called eye cloud. Eye cloud can be caused by bacteria. They cause the eyes of the fish to become a cloudy white color, sometimes almost totally white.

You will notice if your fish has eye cloud when their eyes turn white. They can’t see well when this happens, so sluggish swimming, banging into things, and not being able to eat right are all telltale signs that your fish has eye cloud.

Eye cloud usually goes away if water quality is increased, but for more severe cases, Melafix is a good option.

sick fish
Image Credit: Andrii Oleksiienko, Shutterstock

Tail Rot

Tail rot can be a part of fin rot, both of which are characterized by the fins and tail becoming very dull, sore-looking, fraying, and eventually rotting away. Fin and tail rot can both be deadly if left unchecked because it literally eats away at the tails and fins, leaving fish in pain and unable to swim.

This is often caused by bacteria that are already present in the water. However, regular water changes and a healthy environment help stop the outbreak of this disease. If you notice symptoms, you need to act right away because death is imminent if left untreated.

Mouth Fungus

Mouth fungus is often known as cotton wool disease due to the small cotton-like growths that will appear on the head, around the mouth, and the fish’s gills. Cotton wool disease can be caused by both fungi and bacteria.

If it was caused by bacteria, Melafix is a good solution. It may be able to treat fungal cottonmouth, but maybe not. It really depends on the severity of the issue at hand. This affliction can also be deadly, so act fast if you notice that your fish have it.

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How to Use Melafix

Melafix is actually very easy to use. All you have to do is add 5 ml of it for every 10 gallons of water in the tank. You should do so once every day for 7 days. After 7 days of treatment, you should make a 25% water change. If your fish are still suffering from bacterial infections, you can continue the treatment for up to three of these 7-day rounds if necessary.

If your fish do not get better within 14 to 21 days, you should go seek professional help. On the other hand, if you are just adding new fish to the tank and want to use Melafix as a precaution to prevent breakouts, simply add 5 ml to every 10 gallons of water for the first 3 days after adding the fish into the tank.

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As you can see, Melafix is a great solution and medicine for a variety of bacterial infections in fish. It is a good precaution and a good reactionary medicine too.

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