What is Ich and What do You do About It?

Ich, pronounced "ick", is the abbreviation for ichthyophthirius multifilius, a one-celled parasitic organism that often attacks aquarium and pond fish. The common parasitic disease that is caused by this organism in fish is also called ich. A parasitic disease is a disease that is caused by a parasite, which is an organism that lives on or derives its nourishment from some other living animal or plant. The ich attaches itself to the fish and feeds on it just as a tick or flea would do to a dog.

Ich is one of the most common parasitic diseases that fish get. In fact, the ich organism itself is almost always present in an aquarium, and even on the fish too. Normally, healthy fish in a healthy aquarium would not be affected by low levels of ich and thus would probably not develop the disease. This is because healthy fish usually have very good antibodies, plus a strong slime coating that helps protect them against disease. However, if a fish gets stressed out enough, it will become more vulnerable to ich. The fish's immunity will break down enough such that the ich parasite is able to burrow into the fish's skin to feed and start doing damage. Then your fish has the disease, ich.

You can usually tell when fish have this disease, because the fish will have several small white spots on its body and fins. The spots will be a little smaller than grains of salt. Now, the parasite itself is microscopic and is not visible. The white spots you see on the fish are not the parasite, this is the fish skin's reaction to the parasite, much like mosquito bites or bee stings in humans. You may also see the fish scratching and rubbing itself against rocks and gravel in order to sooth its irritation.

If allowed to progress untreated into advanced stages, ich may cause the fish to become lethargic and even die. In advanced stages of ich, the fish's skin will show redness or even bloody streaks. Even if the fish does not die, the tissue damage caused is a major threat to fish health and can be the site for secondary bacterial or fungal infections. Although the disease is the equivalent of a skin infection, it can easily be fatal to a fish stressed by poor diet or habitat. The disease is also contagious and spreads very easily. Thus, ich must be treated if you want to maintain the health of your aquarium and all the fish in it.

Fish - especially overstressed fish - can get ich easily and can even die from it, but fortunately as you can see ich it is very easy to spot. And it is also quite easy to treat and cure. Medications for ich are readily available at your local pet store and are highly effective. Malachite green, methylene blue, quinine hydrochloride, and mepracrine hydrochloride are some of the most effective chemical medications for treating ich. They are available under several brand names such as Maracide and Quick Cure.

To understand the treatment, it is important to note that the ich parasite lives out its life in two stages: the cyst or single-celled microscopic stage, and then the cell division or free-swimming stage. The ich parasite is in its cyst stage when it first burrows into the fish's skin to feed. In 3 to 5 days it will become mature, release itself from the fish, and fall to the bottom of the tank where it will reproduce by cell division. Just one of these parasites can produce anywhere from 100 to 1000 other parasites, who will then spread throughout the aquarium looking for new hosts to infect, or in this case new fish to dine on! These parasites are now considered in the free-swimming stage.

It is only during the second stage, the free-swimming stage, that you can kill the parasites with medication because they are in the water outside of the protection of the fish's body. Now is your chance to kill them before they all burrow to safety inside your fish again! So, the following are the specific steps to follow in order to treat and cure an ich outbreak:

1. Make a one third water change to make sure that the water quality is optimum. If you are not sure if it is good, bring a sample in to Pet World to get it tested.
   
   
2. If you have tropical fish, remember that the best temperature for most tropical fish is around 78 degrees, although 76 to 80 degrees is still a good range.
   
   
3. Make sure that all filters are working well, with plenty of aeration and circulation. Remove the carbon from the filter before applying medication, as the carbon would remove the medication prematurely.
   
   
4. Add the proper dose of medication to the tank. Be careful not to get any on your clothes or on the aquarium lid or tank, as it is very staining.
   
   
5. Keep the proper dose in the aquarium for at least 10 days, and it will take this long to kill any new parasites.
   
   
6. Monitor the water conditions to make sure they stay at optimum, so the fish can build up their resistance and help fight the parasite.
   
   
7. When it has been 10 days, and you haven't seen any parasites or the white spots associated with them on the fish for at least 4 days, make another one third water change, and add fresh carbon back into the aquarium filter.
   
   

Of course, the best cure for ich is prevention. Try to keep the fish as stress-free as possible. Maintaining high water quality, avoiding temperature and pH fluctuations, and providing a robust diet are the best preventatives for ich and many other fish diseases. For your information, here is a specific list of some of the things that can cause stress in a fish:

• Poor water quality, such as water with ammonia or nitrite.
  
  
• A rapid change in temperature, usually a drop, or water that is too cold. For tropical fish, going from the ideal of about 78 degrees to about 70 degrees or less could cause ich.
  
  
• A rapid change in the pH of the water. pH is a measure of the alkaline or acid content of the water. The water at Pet World is usually kept between 7.6 and 7.8 in pH. If the fish are transferred into water that is either too high, 8.8 to 9, or too low, 6.8 or lower, then this may be enough stress to cause ich.
  
  
• Sometimes, just the trip home in the car can cause the temperature to rise or fall to an 8 or 10 degree difference, and this can cause ich. And if they are kept in the bag too long, such as more than 2 hours, it can cause a build-up of ammonia depending on the fish size, and this can be very stressful.
  
  
• Sometimes an aggressive fish chasing or harassing another fish can be enough stress to cause a fish to come down with ich. This is why you should make sure the fish in your community aquarium are as relatively compatible in size and/or aggressiveness as possible.
  
  
• Poor or inadequate diet.

If you have any questions regarding ich and its treatment, just ask us and we will help you any way we can.

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