My Fish Have WHAT?!?

By Dawn

My dear friend Dawn is MY fish "doctor." When I need advice, she's always the one I call first. She's been keeping fish for more than thirty years, and she still does it the old fashioned way--by doing frequent water changes, stocking lightly and keeping her tanks spotless. She's kept too many fish to list over the years; some of her current stock include leopard discus, featherfins (synodontis eupterus--and are they ever gorgeous), fat and happy clown loaches, bumbleebee catfish, angels, and many cories, several of which she raised--ostensibly to sell to the fish store and which somehow never made it out of the house. --Vicki

If some morning you get up and it looks like someone has salted the body, fins, and gills of your fish, you are looking at "Ich", sometimes called ick, or white spot disease. "Ich" is a protozoan parasite with the scientific name of Ichthyophthirius multifiliis. It is the largest of the ciliated protozoans. It is easily introduced into your tank by new fish or equipment or plants that have been moved from one tank to another. A quarantine tank is the best way to prevent introducing this parasite into your display tank. If you see ich on your fish they should be treated immediately. In heavily stocked tanks it can cause massive death rates within a very short period of time. Some symptoms before white spots appear may include flashing, clamped fins, weakness, loss of appetite, and decreased activity. In the case of heavy gill infestations, you may not see evidence of white spots, but may find your fish breathing heavily at the surface of your tank. Secondary bacterial and respiration difficulties may result, so keep an eye out for complications in addition to the ich infection.

The best way to prevent ich, as I stated above, is to quarantine all incoming fish. A minimum of three weeks in quarantine (in my opinion) is the best way to go. When kept at 76 to 83 degrees, incoming fish that have been exposed to ich may show symptoms within the first 3 days. However, at cooler temperatures, ich outbreaks may take longer to show up because of its lengthened life cycle. Water temperature has a tremendous effect on how fast the life cycle of ich is completed. At water temperatures of 75 to 79 degrees F, the life cycle is completed in about 48 to 72 hours. In water temperatures below 75, it takes much longer for the parasite to complete its life cycle.


There are three phases to the life cycle of this protozoan. Ich is susceptible to treatment at only one stage of its life cycle, so knowing the life cycle is important.

ADULT PHASE: the parasite attaches itself under the mucus layer of the skin or gills, causing irritation and the appearance of small white spots. As the parasite matures, it feeds on blood and skin cells. After some time, the parasite breaks through the mucus layer and falls to the bottom of the aquarium.

CYST PHASE: after falling to the bottom of the aquarium, the adult cyst bursts and divides into numerous daughter cells called tomites.

FREE SWIMMING PHASE: after the cyst phase, the free swimming tomites search for a host. If a host fish is not found within 2 to 3 days, the parasite dies. Once a host is found the whole cycle begins again. These three phases take about 28 days at 70 degrees F but only 3 days at 80 degrees F. For this reason it is recommended that the aquarium water be raised to between 80-86 degrees F. for the duration of the treatment. If the fish can stand it, raise the temperature to 86 degrees. Raising the aquarium temperature in this manner will shorten the length of time between the cyst phase and the free swimming tomite stage. It is during the free swimming tomite stage that chemical treatment is effective in killing the parasite. During this time, whatever you use for treatment should be supplemented with daily or every other day water changes and gravel vacuuming to remove as many adult cysts and free swimming tomites as possible.


There are many different treatments for ich on the market. What you decide to use will depend on which species of fish you are keeping. Some Tetras, Clown Loaches, smooth skinned Catfish, and other species do not tolerate some of the common chemicals used in ich treatments. Make sure to check and see what they can tolerate before treating your tank. Malachite green is one to be wary of, especially with smooth skinned fish such as Loaches, Pictus cats, and Tetras.

Before starting any treatment you should do at least a 25% to 30% water change and vacuuming of your tank.

1) Heat and Salt

One tablespoon of salt per 5 gals. of aquarium water, gradually raising the temperature to 86 degrees F. This is good if you have to treat live bearers who actually like salt as part of their aquarium habitat. Continue with this for a period of 21 days. Adding back 1 Tablespoon of salt for every 5 gals of aquarium water that you remove during water changes. One thing to remember with high temperatures is that you should run an additional air stone to oxygenate the water. There is less dissolved oxygen available in warm water than there is in water at cooler temperatures.

2) Coppersafe (Mardel Laboratories)

This form of copper is kelated and is an effective treatment for fish that are intolerant of Malachite green or Acriflavine, such as Clown Loaches, Tetras, and other smooth skinned catfish. The treatment is 1 teaspoon for every 4 gals. of aquarium water. It lasts 30 days. With water changes you would replace 1 teaspoon of coppersafe for every 4 gals. of water that you are replacing to the aquarium. For the full thirty days. It is important to remember that when you are using chemicals of any kind that you MUST remove the carbon from your filter systems or it will remove the medications you are trying to treat your fish with. I have used this treatment on all the species of fish that I keep, including Clown loaches, Cories, Tetras, and Pictus Catfish and have had wonderful results. Be aware, though, that if you have shrimp or any other invertebrates in your tank, you will either need to remove them or use some other form of treatment; invertebrates will not tolerate Coppersafe. (Note from Vicki: Coppersafe's label also warns that it may harm some plants. However, of those plants in my quarantine tank that have been exposed to Coppersafe, I have never seen any lasting negative effects. Among the plants that have gone through treatment with Coppersafe are various crypt species, hydrocotyle leucocephala, anubias nana, hygrophila polysperma, java fern and java moss.)

3) ContraSpot (Tetra Medica)

This is an ich treatment that is made up of Malachite green chloride and Formaldehyde. It is dosed at 1.5 ml for every 5 gals. of aquarium water. It comes with a marked cup so you get the dose right. It's meant for 3-5 days treatment, with a water change and 3-5 more days at the same dosage if symptoms are still showing. I've used this one too, in my experience I liked Coppersafe results better. If you have to use this one on Clown Loaches, Tetras, Cories, or smooth skinned Catfish you would want to try a half dose.

4) Acriflavine: Ick Care by Jungle

1 teaspoon per 5 gals. of aquarium water. Another dose may be added after 24 hours after a 25% water change. This is another medication that you use only 1/4 dose on small , weak , or scale less fish. It will give your water a yellow tint and is capable of staining your silicone in your tank. There is also a possibility that it could kill plants in a planted aquarium. So, if using this product, it's best used in a quarantine tank, not your display tank.

5) Methylene Blue

If you have nothing else in your medicine chest, Methylene Blue will work on Ich. It was an old time cure for smooth skinned Catfish and Loaches. In the case of Loaches, treating them immediately is necessary as they seem to have a very low tolerance to the ich parasite and have a high rate of mortality if not treated promptly. It is NOT my first choice for treatment, but it could save them until you can get a better medicine for treatment. Follow the label directions. Be aware that Methylene Blue will stain your tank sealant and fixtures, so be sure not to use it in your display tank.

Whatever treatment you choose to use, once it is completed, a good-sized water change is in order (even if you have been doing regular water changes during the course of treatment), and if you have used anything other than heat and salt, it's a good idea to run fresh carbon in your filter for a few days to remove any remaining medication from the tank.

These are some of the medications I have used over my years fish keeping. I hope to add some of the other common fish diseases in the future. Listed below are some fish disease links that I like to consult. I hope this has been of some help. It's just my experience with ich, not anything written in stone. Everyone has to find what works best for them and use it. May you be ich-less!


Diseases and Husbandry

Aquarium Pharmaceuticals - Professional Guide

Aquaworld Net

Pond Enterprises

Information, Please...

Back Home...


Valid HTML