How long does ich stay on fish: Understanding and Managing the Common Fish Parasite

Before knowing “How long does ich stay on fish” let’s get some idea about “what is this disease”.

Parasite diseases in fish are a common problem in aquaculture and wild fish populations. These diseases are caused by a variety of parasitic organisms, including protozoa, worms, and crustaceans.

Ichthyophthirius multifiliis protozoan is a small white parasite usually less than 1 mm in diameter that lives by attaching itself to the fins, body, and gills of fish. After reaching maturity, the fish rapidly metamorphoses, leaving the body and living on the floor or other aquarium surfaces.

After reproduction is complete, the cyst opens and hundreds of new ich protozoa are released into the water, capable of swimming for two to three days until they find a new host to attack.

A fish with ich has tiny crystals on its body that look like someone sprinkled salt on it. Ich can first be seen on the fins of the fish due to the lack of coat on the fins. Also, this infection can be detected by loss of appetite, rapid breathing, the fish rubbing its body surface, lethargy, and hiding behavior. These parasites have the ability to spread very quickly.

How long does ich stay on fish

Causes of Ich

The main reason for the spread of these parasites is that the fish, plants, or something else (substrate, nets) that are added to the tank like ours are not systematically quarantined. The most notable feature of these parasites is the ability to spread to all fish even from one well-grown animal.

They can be observed with the naked eye. However, they go through several stages of their life cycle before being observed, so fish do not show any symptoms until they complete their life cycle. Water temperature also affects the spread of these parasites.

Also, the following reasons can also affect the spread of this parasite.

·         Using infected equipment between tanks without proper sanitation

·         Transferring infected filter media or decor between tanks

·         Movement of contaminated water between systems

·         Adding plants to an aquarium can link cases of Ich to them

Signs of Ich in Freshwater Fish

·         Small white spots on the body or fins of the fish

·         Fish use objects in their environment to lick, or scratch

·         Bruising or scale loss secondary to ignition

·         Lethargy and increased respiratory effort

·         sudden death

How long does ich stay on fish?

At an aquarium’s typical temperature of 78 degrees, the full life cycle of Ich, from the moment you notice it on your fish until it becomes contagious once more, lasts roughly 6 days. If you don’t break the cycle, your fish will keep becoming sick. It is preferable to act quickly to spare your fish the suffering that comes with an ich illness.


Add salt

Add aquarium salt to the water. Salt acts as a disinfectant by slowly releasing oxygen into the water, encouraging parasites to detach from the fish’s skin. AQUARIUM SALT enhances fish health by enhancing gill function, allowing fish to breathe more easily. Fish vary in their salt tolerance and for more sensitive soft water species, we recommend using a maximum of 3-4 tsp per gallon.

Ich X

The dosage of Ich-X according to the instructions is 5 ml of drug per 10 gallons of aquarium water and wait 24 hours. Change one-third of the water and return to the aquarium at a concentration of 5 ml of Ich-X per 10 gallons of water. Remember to add enough medication to treat the entire volume of water in the aquarium, not just the volume of water removed.

Add again every 24 hours until you see no signs of ich. Although the parasite is shed on the fish, it may sometimes remain on the tank’s walls or on other coverings. If you stay like that, the infection can spread again. To avoid it, it is important to remove the water from the tanks and clean all the covers. If there is an opportunity to expose the tanks to the sun, good results can be obtained from it.

Prevent Ich

To prevent Ich or many other parasites and diseases from entering your aquarium, all new additions, including fish, invertebrates, and plants, should be quarantined in a separate tank using separate equipment for four to six weeks.

Even if there are no fish, these parasites can easily live on the plants, so when cleaning the tanks, if there are such plants, they must be cleaned.

To improve the overall health and well-being of your fish and know How long does ich stay on fish, always be sure to maintain good water quality and provide an appropriate diet. Maintain a regular maintenance schedule. Check all your fish regularly and understand their general appetites and behavior so you can quickly judge when something is wrong.

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