The Dreaded Ich

Most of us know what ich looks like and how to treat it. but do we know how ich gets on our fish and how to prevent it? I didn’t so I thought some other people may like to know more about this common fish disease and how to prevent it and what exactly it is. This article is about the freshwater Ich parasite.
What is Ich?
First off I thought ich was a bacteria but it isn’t, it’s a single celled protozoan called Ichthyophthirius multifiliis. Ich is a parasite that feeds on your fish. Ich looks like small squarish shaped white spots that resemble grains of table salt. The salt looking things are actually the adult parasite feeding on your fish. Ich, if left untreated can be fatal.
What is the life cycle of ich?
Ich starts as a free swimming microscopic parasite called a theront it searches around for a host and then attaches itself to the host. Once it reaches adulthood you see it as a squarish shaped salt like grain on the fish. This stage of the ich parasites life cycle is called a trophont. The parasite continues to feed on your fish, constantly moving and turning under the skin it feeds on the destroyed tissues and fluid. this is possibly what causes “itching” and why your fish may scrape on decorations or rocks trying to scratch itself. The white squarish thing you see is actually an outer casing of sorts where the parasite is attached to infected fishes skin and slime coat, as the ich parasite grows it gets so big it breaks out of the cyst and falls to the tank bottom where it becomes encapsulated and begins to internally divide into hundreds of ich parasites, this stage of its life cycle is called tomont. It takes about a week for the ich parasite to complete its life cycle, which is why quarantine is so important.

Theront-the ich parasite spends 2 days in its free swimming state, if it doesn’t find a host it will starve and die.

Trophont-the ich parasite spend 4 days in this state feeding from the host into adulthood so that it will have enough food to make more parasites.

Tomont-it only takes the ich parasite one day to stay in this stage and make hundreds of little parasites that can swim out and infect other fish or come back and feed on the same untreated fish.
How can I prevent ich?
Mishandling, rough netting or injury may all disrupt your fishes slime coat. The slime coat of your fish protects it from the ich parasite. Stressing your fish with other problems such as bad water quality, improper PH, temperature and poor diet are all things that can affect your fishes health and make them more vulnerable to the ich parasite. Quarantining your fish for a 2 week period and paying special attention to the smoothness of their body can help. Ich appears to be more common in the spring and fall, possibly because of the change in room temperature. The temperature change can be sudden and possibly result in your fish getting chilled, just as people do when they go outside without a jacket unprepared for cool weather. Neon tetras and koi appear to be two of the least resistant fish to the ich parasite.
How do I treat for ich?
Check your tanks water quality and appearance for anything abnormal. Make sure your filter media is rinsed or replaced and then choose a medication. I prefer quick cure but there are other medications you can use. Coppersafe, Super ich cure and ich Guard are a few. Invertebrates do not tolerate these treatments well and should be removed before dosing the tank. Be sure to change the water before beginning treatment and closely follow the directions on the medication. Also delicate plants may suffer from this medication so should be taken into consideration as to their removal. If your fish are showing signs of distress after dosing such as gasping, abnormal or erratic behavior, you can quickly give your tank a couple of good squirts of Amquel to neutralize the malachite green, add the carbon back into your filter and perform a series of partial water changes to normalize the situation.

Here is a neat slideshow that shows the different stages of ich and also some microscopic pictures of the ich parasite.