Ich In Fish

What Is Ich

Ich, otherwise known as freshwater white spot disease or freshwater ich (ick), is caused by a protozoan called ectoparasite.

sick fish

 It is one of the most common and persistent diseases that attack freshwater fish. There is no dormancy period for this disease.

But anything that stresses your fish can cause an outbreak. It’s best to keep your fish very stable, the tank environment staying steady is the best prevention of the disease.

 There are three basic life stages of the Ich protozoan.

  • First, is the feeding stage where a nodule forms in the skin or the gills.
  • Second, it enters a dividing stage that throws off cells that adhere to plants, nets and other tank items.
  • Third, more rapid division of the cells on the fish that further attack and can be fatal.

How Long Does Ich Last

How long the life cycle of the ich, is completely dependent on the temperature of the water, but can take 7 days to 8 weeks.

 Ich is very damaging to fish that are able to survive.

damage done to the tissue and gills can be very hard to overcome and often fish that survive initially, will not last too long and eventually die off.


 If they do survive, they will develop a bit of an immunity to getting the disease again.

How Do I Know If My Fish Has Ich

You’ll know your fish have contracted this disease when you notice the small white spots that appear.

No bigger than a grain of salt or sugar, they attach to the fishes body and take over.

 This organism is very easily introduced into your tank by means of newly introduced fish or equipment that has been used in an infected tank and then used in a new tank.

Because this disease can take over a tank very quickly, you will want to be very diligent in cleaning your tanks, keeping cleaning tools sanitized when using between tanks, or even keep a set of tools for each tank separately.

 The best way to keep this disease from jumping tanks and killing fish, is to sanitize all equipment used from one tank to another.

clown fish

The easiest way to sanitize is boiling equipment in hot water for a period of 5-8 minutes.

You can also quarantine new fish for a period of at least two weeks and plants for at least 4 days to make sure the new fish are clean and healthy.

 When bringing in new fish or plants, quarantine them in a separate tank, transfer them from the water they came home in and put in clean water in your already stable quarantine tank.

This will greatly reduce the chance of bringing ich into your home tanks. At the pet store, only buy plants from tanks that have no fish in them.

Treating your water to prevent this disease will not be realistic if you don’t take heed of the preventative measures above.

How To Treat Ich

If you do have an outbreak of Ich, treat your tank immediately and aggressively. The following will help you to eradicate the Ich disease.

First off, take all the fish out of the tank. Without any bodies to attach themselves to, the disease cells will die off in about 48 hours.

Then you can heat treat the tank. Raise the temperature to 85 degrees for a period of 4 days or 96 hours to kill off any remaining bacteria.


You can raise it quickly in an empty tank, however, in a tank that you are leaving fish in, raise it gradually throughout a couple of hours or your fish will become even more stressed and have less of a chance of surviving.

If you choose to leave your fish in the tank while heating it up for treatment, add extra aeration because warm water can‘t hold the same amount of air as cold water.

Extra aeration also helps your fish to not suffocate.

 This would happen because the ich attacks and attaches to the gills. You will want to use this heat treatment hand in hand with another treatment to be more effective in treating the disease.

 Add in a teaspoon of canning and pickling salt to help the fish recover even quicker. When treating ich, water changes are of utmost importance.

Use a gravel vacuum to do a 50% water change on a daily basis.

Ich is such a common disease that many pet stores take the quick and easy alternative of killing it with the use of chemicals.

Because of this practice in pet stores, the home tank will sometimes need to be treated in the same manner. There are commercial chemical Ich treatments available if all else fails.

Lastly, change, get rid of or clean aggressively any gravel or rocks in your tank along with decorative items.

Ich tends to stick to surfaces and some people overlook the most obvious places that the Ich will try to hide.

yellow fish swimming

Once all medications and salt treatments are finished, do smaller water changes slowly to bring back a stable tank. 

Exposing fish for a greater amount of time than is necessary can be damaging and harmful to your fish.

 Be aware that not all fish can tolerate such high temps, so if you do decide to leave them in the tank while treating it, research the highest temp your fish can handle without stressing even more.

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