Ich Symptoms
Ichthyophthirius multifilis is the fish parasite popularly known as "ich" or "white spot." Ich is one of the most commonly diagnosed parasites that can affect a goldfish community. Observing the ich parasite on a mucus scrape from an infected goldfish under a microscope can reveal the two life stages of ich. During the "swarmer" stage, Ich is a highly active, free-swimming, teardrop-shaped organism with a green or tan colored interior. The sub-epithelial life stage shows a large, round organism with fine cilia and a visible horseshoe-shaped nucleus.

A microscope is rarely needed for an accurate diagnosis as the infected goldfish will more often than not show visible symptoms. The most obvious symptom of ich is the sign of tiny white spots on the body and fins of an infected goldfish. These white spots are not ich parasites; they are a reaction of the immune system attempting to fight off the infection. In certain cases of ich, depending on the strength of the immune system, a goldfish will not get any white spots. Certain physical and behavioral changes of a goldfish can help diagnose ich when white spots are absent. These changes might include: isolation, lethargy, clamped fins, difficulty breathing or redness of the skin.

The Causes of Ich
An infestation of ich in a goldfish tank often occurs within the first week of introducing a new goldfish that was not properly quarantined. If the ich parasite is introduce into a goldfish tank via a new goldfish, goldfish with healthy immune systems can often fight off an ich infection but goldfish that have weak immune systems are susceptible to an infection. A weak immune system can be the result of a weakened protective slime coat caused by stress or from an infection the goldfish is currently attempting to fighting off.

How to Prevent Ich
Many goldfish dealers will quarantine new shipments of goldfish they receive but it is not a given these goldfish will be 100% free of disease. It is best to err on the safe side, quarantine and isolate new goldfish for two to six weeks in a separate tank from the main goldfish tank. Some fish stores offer in store quarantine of the goldfish purchased by their customers, for a fee. Whatever option is chosen, all new goldfish should be observed for a period of time to ensure they are free of disease.

Keep the stress of the goldfish low by choosing similar goldfish breeds to be tank mates, have appropriately sized filters and air pumps for those breeds and provide plenty of places to hide. Maintain optimal water parameters including: plenty of dissolved oxygen, pH around 7, water temperature around 70*F (21*C) and a healthy functioning nitrogen cycle.

How to Treat Ich

1. Remove live aquatic plants. The treatment can harm or kill live aquatic plants.
2. Preform a partial water change and achieve optimal water parameters.
3. Temporarily increase the water temperature to 75-80*F (24-27*C). This encourages the ich parasite to speed up its life cycle. The sub-epithelial ich parasites will burst out of the skin and fall to the bottom of the tank where thousands of new free-swimming parasites will search out a host. It is only during this swarmer stage that ich can be treated.
4. Add a .03% concentration of aquarium salt; one teaspoon per every gallon of water. Aquarium salt is readily available at local pet stores. It is important to treat the entire tank not only the infected goldfish. Avoid using a quarantine tank.
5. Over the next 24 hour repeat step 4, in 12 hour increments for a total of three doses of aquarium salt. (It is common for ich to get worse before it starts to get better.)
6. Leave the aquarium salt in the treated goldfish tank for two weeks then preform a 50-75% water change.
7. Add a protective stress coat solution to encourage a healthy slime coat and immune system of the goldfish.

Information courtesy of HowtoTakeCareofaGoldfish.com

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