A Convincing Explanation For “How Long Does Ich Stay On Fish?”

Most fish owners will eventually have to cope with the white spots, a general and difficult-to-treat fish condition brought on by the parasite ich.

How long does Ich stay on fish? If the temperature is favorable, your pets may struggle with this parasitic infection for around three weeks.

It’s best to get an overview of this disease and have immediate solutions. Let’s dig into this post to learn more!

How Long Does Ich Stay On Fish?

The period this bacteria stays on your pets depends on the tank’s temperature.

This bacterium may live on your pets for around three weeks when the temperature is at 9 – 10℃. When the temperature reaches 24 – 25℃, its life cycle will shorten, around six days.

You must maintain the medication for five to seven days to eliminate the parasite from your pets.

Otherwise, your fish may suffer skin injury, resulting in death, making it a significant hazard to tank species.

The scientific name of the bacteria is Ichthyophthirius multifiliis. White spot illness and ick are both terms for this parasite.

The parasite spreads throughout the fish’s blood after entering through their mouth or gills.

The parasite may mature and start eating your pets if the appropriate treatment is not performed promptly.

When fully grown, it drops off your pets and quickly reproduces. The cyst bursts out, letting thousands of parasites search for new hosts in your tank.

This parasite has tiny size, only approximately 1mm. However, it is very contagious and has the potential to infect your whole aquarium.

For this reason, immediate treatment is essential after you have noticed some white spots on your aquatic pets.

ich on fish

What Causes Ich On Fish?

The most prevalent culprit of this parasite is failing to isolate a new species you have brought to a community tank.

One contagious parasite is enough for a complete tank to get infected.

Until the parasite has gone through a couple of life cycles, most aquatic pets will still appear healthy and not exhibit any symptoms of illness.

Depending on the temperature of your tank water, identifying the signs might take several days or even a couple of weeks.

If introducing the new species is the leading cause, it’s best to safely quarantine them to prevent the parasite from spreading to the main tank.

Apart from this main reason, some other additional factors cause this disease, including:

  • You use infected tools between aquariums but lack proper sanitation.
  • You accidentally transfer an infected filtration system or décor items among tanks.
  • You constantly move infected water among tank systems.
  • You add aquarium plants to your tank, but they may carry parasite tomonts.

fish in tank

Common causes

What Are Signs Of Ich On Fish?

If you want to realize the signs of this parasite, you must know how to tell it apart from Lymphocystis, which is a white bump on fish skin.

It’s an incurable chronic illness that affects freshwater and saltwater species. White spot illness is the fundamental distinction between them.

If your pets have parasite infections, these white spots are evenly distributed on the fish’s body. Whereas, Lymphocystis typically focuses on one area.

The spread of this parasite to encompass the entire fish occurs swiftly and within one week, another critical distinction.

Compared to Ich, Lymphocystis causes these lumps to develop more slowly. Below are typical symptoms of this bacteria you should know:

  • Color loss
  • Lack of appetite
  • Small white spots on your fish’s body
  • Rough skin, open sores, or scabs
  • Sluggish and requiring more effort to breathe
  • Death of several fish in the tank
  • Rubbing to the tank’s wall or ornamental items
  • Fish swimming near the tank’s substrate or on the water surface

How To Treat Ich On Fish?

Before applying treatment, it’s best to inspect your pets to determine whether they get parasites.

If you are unsure about the illness conditions of your pets, you should get the help of a vet.

After having an exact diagnosis, it’s time to treat bacterial infections in your pets.

The first thing is to remove the species infected with this parasite from the community tank and transfer them to another hospital to conduct treatment.

If a quarantine tank is impossible, you can apply medication to the whole aquarium to treat parasitic bacteria.

The optimum course of action is what follows:

Step 1: Buy Ich-X

This medication is a mixture of tank solutions.

It has a less hazardous version of the chemical Malachite Green, which is toxic to species and the aquatic environment.

That’s why it causes no harm to freshwater species, even if it’s sensitive creatures or beneficial bacteria.

Step 2: Clean the tank

Before applying Ich-X, make sure you properly clean your tank. You should change the water, vacuum the gravel, and clean the filters.

Because the parasitic organism might cling to the tank viewing screen, you must clean it on the interior and exterior.

Step 3: Eliminate any chemical filtering

Discard the aquarium’s chemical filtration system and any activated carbon that is still there. You can use these after therapy.

Step 4: Treat Ich

Add Ich-X at a dosage of one teaspoon per every ten gallons of water.

Step 5: Wait 24 hours

Give the initial dosage one day to take effect.

Change 1/3 of the tank’s water, then do the same proportions again.

Step 6: Repeat the steps until there is no white spot left.

The process may last five to seven days.

Step 7: Remove Ich-X

If the parasite bacteria doesn’t stay on your pets, perform a water change to remove the medicine.

Remember to maintain water changes once monthly. If you are inexperienced, you can click on this video:



Will Ich Go Away On Its Own?

The answer is no! It could come off to grow again, eventually eating your pets.

Can Fish With Ich Survive?

Your pets can’t survive if you don’t apply treatment immediately.

Can Healthy Fish Fight Off Ich?

Yes! If these aquatic creatures are healthy and strong enough, they can fight off this parasitic bacteria as they do in nature.

Can You Feed Fish While Treating For Ich?

You can give them food as usual if they desire to eat.

Can Ich Live In The Filter?

Yes, this parasite can attach to anything in your aquarium, like filter media, heaters, rocks, socks, or sand.

Final Thoughts

How long does Ich stay on fish? It may live on your pets from six days to three weeks, depending on the tank temperature.

Although these white spots look harmless, they can lead to the death of the species if the infection is severe.

Hopefully, you can successfully treat parasite infection with our comprehensive guides. Thanks for taking the time to read this post!