How Long Can Fish Live With Ich? [Explained In Detail]

Ich in fish is a fatal disease for them. You must know what causes it and how to prevent it. But how much time are you getting to save them? So this question comes to mind-

How long can fish live with ich?

No fish can live with ich for long. Fish can live with ich for 2 weeks at most. If proper treatments are not taken soon enough, they’ll unfortunately die.

Fishes with strong immunity may hold out for a week or more. But the weaker ones will start to die from days 4-7.

That was the surface idea of this topic. Care to know more? Then keep reading till the end because we have the necessary info here.

What Causes Ich In Fish?

The ich in fish is generally caused by a parasite that lives inside them. This parasite is called Protozoan. 

Usually, it attacks fishes with frail immunity. Once they get attacked by it, white spots start taking place on their body. The spots are a bit similar to the blackspot in clownfish but white. 

That’s why it’s commonly named white spot disease. The scientific name of this disease is called Ichthyophthirius multifiliis. 

There are a few reasons why fishes catch ich. It mostly happens due to the stress of fish.

The ammonia in the aquarium water is what causes a fish to stress. It weakens their immunity. 

When this happens, the antibodies to repress ich also weaken. Keeping fish at low temperatures (below 75°F) is also another cause. 

How Long Can Your Fish Live With Ich?

Ich is uncomfortable for any living being. But imagine how bad it can be for fish. 

You’d see these poor creatures trying to rub their skin on aquarium glasses. What’s more alarming is that ich can kill it. Fish can survive 2 weeks at best with ich.

There are three stages of development of this ich in an aquarium-

In the first stage, the parasite enters the fish’s body and develops white spots. These spots are itchy. So, fishes would rub their skin on aquarium glass or decorations. 

This stage continues for 5-6 days. During this time, the parasite stays on the fish’s body. 

You’d see your fish getting lethargic from the parasite attack. Fishes with weak immune systems might even die from this.

If the first stage goes untreated, the parasite matures. Then it comes out of the fish’s body and starts to multiply exponentially. 

This stage continues for 2-3 days. The ich would be seen in the water at this stage. This is the most dangerous time for fish because these parasites can easily attack other fish. 

Lastly, they take over the whole community, and the situation goes out of hand. So, it would be best if you started the treatment at the first stage.

When you see one fish getting affected from ich, start the treatment right away.

Delaying the treatment will only reduce their chance of survival, especially if your fish has a weak immune system.

What Are The Treatment For Ich?

There are a couple of methods available to treat ich infected fish. These methods are simple and easy.

Mostly you’d have to combine these methods when treating your infected fish. 

Now, let’s take a look at some of these methods.

Method 1: Heat Treatment

Ich abhors warm water. So, raise the water’s temperature by 30°C (86° F) immediately.

If you want, you can upgrade your bio cube light for this. 

Ich can’t reproduce at temperatures higher than  30°C or 86° F. However, this method is not for cold-water fish.

Method 2: Using Medication

This method can be applied in combination with method 1. There are many medicines available in pharmacies for ich medication.

Most include formalin, malachite green, methylene, which is effective against ich.

Method 3: Salt Treatment

Ich can’t handle salt. So, mix 1 teaspoon of aquarium salt in 3 gallons of water. 

Remember to use it in moderation. Because not all fishes can adapt like mollies that live in saltwater, combine this method with method 1 for a better outcome.

Method-4: Quarantine Treatment

Take out the infected fish from the aquarium and place it in a quarantine tank.

Now, you can choose any kind of treatment suitable for the fish. You can even combine all the methods mentioned above.

This way, the whole fish tank won’t be contaminated with ich.

How To Prevent Ich Attack In Fish?

The parasite can enter your tank in various ways. If you’re conscious, you might be able to prevent it from entering the tank. 

There are a couple of things to keep in mind. These are-

Do Not Introduce New Fish

Do not randomly bring in a new fish. Ich can come from the new fish to the tank. 

So, the new fish should be placed in a new tank. Or you can keep it in quarantine for some time. Then release it to the main tank.

Clean New Elements For Aquarium 

Be it a plant or decoration for your aquarium, first clean it. Store-bought materials can bring in ich. So, thoroughly clean them before setting the decor in the fish tank.

Lastly, keep your fish stress free. It’ll boost their immunity.


Question: How long does ich last after starting the treatment?

Answer: Once you start the treatment, it’ll take 4-7 days to see any improvements.

If the situation is difficult, you might have to switch the medication or treatment methods.

Question: How to use salt for ich treatment?

Answer: Apply 1 teaspoon of salt in 3 gallons of water. It’s better if you do it in the quarantine tank.

Because not all fish have the same salt tolerance. Lastly, raise the water temperature for better results.

Question: Can fish ich affect humans?

Answer: No, it isn’t a threat to the human body. But it’s better that you don’t touch the ich contaminated water or fish. And if you do, wash your hands thoroughly afterward.


That was all from us about how long can fish live with ich? It’s a serious problem for your tiny aquarium pets.

So, always be careful with them. Hopefully, now you know what to do to prevent them.