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Ich (White Spot) What it is and how to cure it by: LesGerber

ICH (White Spot)

While there are several diseases that the aquarium hobbyist has to deal with, Ich or White Spot is among the most common. In this article we will discuss Ich, how, why, the life, and treatments of it. Hopefully after you are finished you will have a better understanding of this disease and feel more comfortable in its treatment. First off we are going to look at the scientific side of the disease so that we better understand what it is doing.


Ich, whoís scientific name is Ichthyophthirius multifiliis and it is a protozoan parasite. As in anything a parasite is a creature that feeds off a host to complete its life cycle. The Ich attaches itself to the fish as a tick would do a dog. After attaching it continues to feed until it is complete.

The life cycle of the Ich is a complex one, as by the time you see it on your fish it is already in the adult stages of its life. The general consensus is that Ich has a lifespan of about 10 to 14 days, while there are those in the science world that will go as far to say the lifespan will be as long as 20 days. When you first see Ich it will appear as grains of salt on your fish. By the time that you see it as stated before itís in its final stages and ready to reproduce. After falling off of the host, it becomes free swimming and will fall to the bottom of the tank or attach itself to rocks and decoration in the tank.

Once the cyst settles in begins to multiply by dividing itself up to as many as 2,000 times. The result of this division produces what is called Tomites. The time frame for this division can vary. In a tank that is 77 degrees F, the tomites will only require about 12 hours to complete this stage as where in a tank of 50 degrees F it may require months to complete.

After the formation of the tomites is complete, they emerge from the cyst as free swimming Theronts. At this stage of their life they are looking for new hosts to feed on. After finding their new host, they will penetrate the fishís skin and then become Trophozites where the cycle of life begins again. If a Theronts is unable to find a new host within 24 they will usually die.

So now that we have a general idea of what Ich is dong in our tanks lets take a look at what we can do to stop it.

Treatment and Prevention

While totally preventing this parasite is hard to do, most every aquarium has Ich in it, and it is not uncommon to see ich at the local fish store, there are several things that the aquarium hobbyist can do to help prevent an outbreak. First thing a person should do is look around at all the tanks at the LFS. Make sure that all the fish are healthy. Also take the time to look to see if there are any signs of ich in any of the tanks. Most if not all LFS have their tanks set up on a centralized filtration system, which means that is there is ich in one tank then more than likely there are free swimming tomites in all the tanks. In my opinion there is no better prevention than checking out all the tanks in a store before purchasing even one fish. Second thing, after everything checks out and you take you new fish home, Take your net and scoop the new fish out of the bag from the LFS and put the fish in your tank. Dump the water in the bag down the drain. There may very well be free swimmers in the water and no one knows and by doing this you help cut down the chance of loading your tank with Ich.

You have done everything right and low and behold is that Ich you see, donít freak out. It does happen, so lets move on to the different ways to treat it.

When treating Ich there is only certain times that the parasite is vulnerable to treatment, knowing this will ease the stress for you. The only times that the Ich can be treated are when they are in the free swimming stage of life. When you see it on your fish there isnít a lot you can do at this point. If you recall we talked about the Tomite stage. This is the point in which treatments work. There are various treatments you can use and there are many great products out there. RID ICH is a very popular treatment that contains Malachite Green. What makes RID ICH different from other products containing Malachite Green is that the levels of it are not as strong as other products and it is safer for scale less fish.

By no means am I saying that this is what you have to use, rather in my experiences with Ich this is the product I have used with great success.

Water changes can help too at the first sign of out break; if you are seeing lots of ich then you can be sure there are tomites swimming around. There a lot of people that advocates the changing of water on a regular basis when treating Ich. I for one feel that if you are treating the water like you should (you will see below) then water changes are going to run you the risk of starting a mini cycle which is just as stressful to the fish.

Another way of helping rid your tank of Ich is to turn up the temperature of the tank to 82 degrees. The Ich parasite is very much a parasite thatís life cycle is varied on water conditions. The warmer the tank the faster they grow and faster the treatment can work. There are reports that Ich cannot survive in temperatures over 85 degrees. While I do not recommend you turn your tank up that level to just get rid of ICH, raising the temperature will help you cure it sooner.

Another thing that can be done to help with the treatment of ICH is adding salt to your tank. Most LFS carry aquarium salt and it serves in helping gill function and works as a general tonic to fish. BE WARNED The use of salt in tropical aquarium is highly debated. There are many species of fish such as catfish and loaches along with several other scale less fish that cannot tolerate high levels of salt. While it has been my experience that salt in small amounts are good you have to use extreme caution when doing so. Always use much less that the recommended amounts on the box. Start out with ľ of the amount and see how the tank reacts, and be ready to pull water out if your fish show any strange reactions.

Treatment Times

Most products donít really give you a good time frame for using their product. With that in mind I will give what I recommend to give you and idea. After you first notice Ich you need to treat. It is my opinion that you need to treat daily for at least 10 days but I prefer 12. After that time then I will go to every other day for a treatment until I have reached the 16 day mark. Another thing to remember here is that you need to treat regardless of time for at least 3 preferably 4 days after you see the last White Spot fall off. With my method you will have every parasite dealt with by the end of the 16th day.


So to recap, after you see Ich on your fish the first thing you are going to want to do is turn the temperature up in your tank to about 82 degrees. If you have a heavy outbreak then do a 10 to 20% water change to help remove some of the tomites. Next youíre going to want to start water treatments with the Ich medicine of your choice and continue to treatment for a minimum of 16 days or 3 or 4 days after the last white spot falls off.

Doing these things will help get your tank back to where you and your fish arenít as stressed and every ones happy

Reference to La Don Swan, Illinois/Indiana Sea Grant Program, Purdue University and Scott Fitzgerald D.V.M, Animal Disease Diagnostic Laboratory, Purdue University Sea Grant # IN-IL-SG-E90-2

For a more broad article on all types of fish disease click here

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