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Saltwater Ich Treatment in Reef Tanks

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Last updated on September 28th, 2022


Saltwater Ich Treatment in Reef Tanks

Saltwater Ich Treatment in Reef Tanks

Saltwater Ich Treatment in Reef Tanks is a key topic for anyone with a saltwater fish tank. It is likely that at some time during the hobby, you have or will see a fish in your tank become affected. The bad news is that once the parasite is in your tank, the only way to get rid of it is to remove all of the fish from the system. Treating the fish and the tank seperatly. Otherwise, even though the fish may recover, ich can come back at any time. Usually affecting new additions and other fish stressed by the new addition.

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If you know what you are doing, and just want the instructions on a specific saltwater ich treatment, feel free to skip to the section you need. If you are as confused or concerned as I was when I lost a fish to saltwater ich, you may want to read the entire article and get a better understanding of what you are fighting, how you can best handle it, and why that method is best for you!

What is Saltwater Ich - The Marine Ich Lifecycle

Saltwater ich, also known as saltwater ick, or white spot disease, is a parasite that attaches and feeds on fish. This parasite does not affect invertebrates nor coral. The saltwater ich parasite has 4 main stages of life as shown below.

The first stage when marine ich is noticed is known as the "Trophont" stage. This is the time when you see spots on the fish. The trophonts will burrow in to the fish, feeding on the fish for up to 9 days. You may not notice the parasite if it is focusing on the fishs' gills.

The next stage of the marine ich lifecycle is the "Protomont". This is the phase where the saltwater ich parasite drops off of the fish and swims for as long as 18 hours to find a surface within the tank where it can reproduce. This is the time when most believe they have cured marine ich. Unfortunatly, it is really when the ich parasite multiplies...

While reproducing the saltwater ich parasites are known as Tomonts and Tomites. The Tomont is the parasite that dropped of the fish to reproduce, and the tomites are the 200 or more children parasites it forms. These cells can incubate for anywhere from 3 to 72 days. This means your tank can have ich sitting dormant for 2 and a half months without food.

Finally, the Theront stage, is when these cells start the cycle again. Swimming freely in the water column for as much as 2 days looking for a fish to host. And it all begins again. This cycle can be as long as 84 days before the ich on an infected fish may multiply and attack again.

Saltwater Ich Treatment for Fish

When treating saltwater ick, you will need to treat the fish seperate from the display tank system. Even fish that are not currently showing signs of saltwater ich could become sick at any time. It is especially common for the parasite to attack during times of stress. By treating all of the fish as if they were sick means that it will remove any parasites and illness that the fish may have. There are a number of ways to treat saltwater ich. Here are some of the most common.

Freshwater Dip

Using a Freshwater Dip is a frequently discussed saltwater ich treatment in reef tanks. This method includes removing the fish from the reef tank, and dipping them in fresh water for no more than 5 minutes in well airated, heated RO water. This method is used to help reliev saltwater ick from the fish, however it will not work as a long term saltwater ich treatment. The best case scenario is that the saltwater ich on the fish dies, but it is still in the aquarium. So it may be gone for a while, but it will come back.

Hyposalinity for Saltwater Ick

Hyposalinity, also known as Osmotic Shock Therapy (OST), is a well known saltwater ich treatment. Hyposalinity is an especially good saltwater ich treatment for sensitive fish. Hyposalinity is defined as a specific gravity of 1.010-1.013 (salinity of 13-17ppt). Saltwater fish can live in this salinity level, but saltwater ich cannot.

Unfortunately, Coral and invertebrates also cannot live in hyposalinity. This means, like most saltwater ich treatments, that if you have a reef tank, you will need to remove the fish completely and use a quarantine tank. If you have a FOWLR tank though, you may be able to use hyposalinity in your display system itself.

Hyposalinity works because saltwater ick cannot regulate the cell walls with the change of salinity. This causes the saltwater ick parasite to essentially explode. Some species of saltwater ick have been known to survive through hyposalinity. That being said, you can use hyposalinity in addition to another saltwater ich treatment and handle a wide variety of illnesses at the same time.

Unless hyposalinity is maintained in the display tank, the saltwater ich on the fish in quarantine will die, but it is still in the aquarium. So it may be gone for a while, but it will come back. Holding hyposalinity in the display tank is a valid saltwater ich treament, but it will kill most invertebrates, corals, and can affect your biological filtration. As such, it is best to only use hyposalinity in quarantine tanks.

Treating Saltwater Ich with Copper

Copper is a common saltwater ich treatment, however it is toxic to reef tanks. Copper will kill invertebrates such as snails, hermit crabs, shrimp, and even anemones and coral. It may seem like an acceptable treatment in the main tank, as coral and invertebrates are easier to remove than fish. Unfortunately, this could mean never having invertebrates or coral again.

Many copper treatments will be absorbed in to the rock and/or sand. This means you should NEVER use copper in a reef tank, as it will leach out and can kill new additions. The solution? Quarantine Tanks. Using copper as a saltwater ich treatment in reef tanks requires that you move all fish, not just the sick ones, to a quarantine tank and treat the fish with copper there. This will prevent killing everything in your main tank.

When using copper as a saltwater ich treatment, you'll need to treat for a minimum of 2 weeks. You will want to quarantine all of your fish for 2 weeks after the last visible spots from saltwater ich disapear. The amount of copper you need in your quarantine tank will depend on the copper product you use. Copper Power is considered one of the safer copper treatments to be used with saltwater ich infected fish. The copper levels when using Copper Power is 5 times higher than the most popular product, Seachem Cupramine. Regardless of which copper solution you choose, make sure to follow the directions to keep your fish safe.

If you are looking for a good copper tester, without the color comparison guess work, check out the Hanna Instruments Checker Copper High Range Colorimeter.

Tank Transfer Method

Tank Transfer is a chemical free saltwater ich treatment in reef tanks. The concept is fairly simple but you will need at least 2 tanks. Unlike hyposalinity and copper treatment, this saltwater ich treatment focuses on moving fish from one tank to another timed to the different phases of the ich lifecycle. Essentially the concept is to move the fish to a new, clean tank as the parasites fall off. Then draining the old tank. Though this method works most of the time, it is possible for some of the parasite to survive as the premise is based on timeing.

So how do you do the tank transfer method? It's quite simple really. To start, you will need 2 tanks with identical temperature and salinity. You will place all affected fish in the first tank. On the 3rd day (but no more than 72 hours), move all of the fish to the second tank. You will then turn off all equipment heaters and air stones, and completely drain the first tank, and rinsing it out. Then you will set it up identically to the other tank. On the 6th day (no more than 72 hours after the last transfer) you will move the fish to the other tank. You will repeat this for a minimum of 14 days, but ideally over 30.

I think it's obvious why this method isn't ideal. The water from the other tanks cannot be re-used, nor added to the opposite tank, as it could contain parasites. Additionally, you can't use filtration or sponges because the saltwater ick parasites could be living in them. Though this could be done by setting up 5 to 10 tanks. That way you can move the fish along. However you will still need to either drain and rinse each tank after the fish leave to the next, or let them sit empty for 30 days without fish.

Killing Saltwater Ich in the Tank (not on the fish)

As you likely read above, in "What is Saltwater Ich - The Marine Ich Lifecycle", the lifecycle of the Saltwater Ich parasite can last for up to 84 days. The unfortunate part is that the only times when saltwater ich can be treated are when they are in the water column or on the fish. But for the 3 to 72 days (you read that right) there is nothing you can do. This is why there is no great way to handle completely remove the ich parasite from the tank.

There are a few ways that can help you in either maintaining a low number of ich parasites, or possibly destroy them all!

Saltwater Ich Treatment in Reef Tank - Maintain Fallow Reef Tank

Starting with the only saltwater ich treatment in reef tanks to ensure total removal of the ich parasite. Keeping the tank fallow, meaning abosolutly no fish, for 90 days means the parasite will have no food and die. The reason for the 90 day time frame is that the marine ich parasite can live for 84 days, only a small piece of that is the time in which the parasite is infecting a fish. Assuming it is possible that some of the parasites are freaks of nature and live an extra couple days, the 90 day window should essentially guarantee success!

During this time, you can quarantine and treat the fish from the reef tank using 2 to 4 week phases of multiple treatments above!

Ultraviolet (UV) Treatment

Another frequently used saltwater ich treatment in reef tanks is the use of a UV filter. UV filtration, with a slow enough flow rate, can kill saltwater ick parasites. Unfortunatly, this will not kill all of the marine ick parasites in the reef tank. The UV filter can only kill parasites that flow through the UV filter for enough time to kill it. It won't do anything for the parasites that are in the sand, on the fish, or in the water column and not passing through the filter. Though UV may slow down marine ich, it will not remove it completely.

Reef Safe Saltwater Ich Medication

There are some reef safe saltwater ich treatments on the market, such as Kick Ich. This solves all of the problems, doesn't it?! Don't get too excited. Though it is possible for the medication to work, it only affects ich in the water column. Making it nearly impossible to kill all of the marine ich in the tank. The cost of most of these medications can be fairly high if you have a large reef tank as well! If you have a reletively small, and simple reef tank setup, or don't have an easy way to set up quarantine tanks, it may be worth trying however.

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What would I recommend? Well, I am actually writing this article in response to trying a variety of these saltwater ich treatments and looking for additional methods. I have found that in my system, the reef safe medication method unfortunately did not work. Additionally, the UV filter slowed the parasite, but as soon as I added a new fish, both the new fish and multiple others had an outbreak of marine ich. With coral and invertebrates in my system, I cannot use hyposalinity in the display tank itself. So what did I do?

I am removing all of the fish from the main tanks, setting them up with quarantine tanks, and treating them with multiple methods. I am starting with 2 to 4 weeks of hyposalinity, and then 2 to 4 weeks of copper treatment. All of this during the 90 day fallow period to treat the tank itself.

Saltwater Ick Treatment Products

Here are the products recommended in this article:

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About the Author

Reef Stable Founder John Krenzer

John is a Software Engineer with a passion for saltwater aquariums, as well as the founder and president of Reef Stable. He started in the aquarium hobby as a child with a 20 gallon freshwater aquarium. His interest in aquarium life grew and in 2008, John set up his first saltwater aquarium.

Today, John maintains an over 300 gallon reef tank system, consisting of a 120g reef and a 210g reef. These large tanks are contained within the same system, sharing a sump as a means to reduce total maintenance and increase total water volume.

John writes articles for the blog as a means to learn about more reef aquarium topics. These articles act as a reference for the readers as well as himself. John updates these articles frequently to provide additional information or make corrections as new information becomes available.

If you would like to request an article, tank tour article, or to colaborate, let me know via the Contact Me Page!

About Reef Stable

Reef Stable was initially founded in 2019 as a reef tank parameter log to fill a need. Reef Stable quickly grew, becoming a location to solve all of your reef tank problems as well as a place to learn.

Reef Stable now provides a Reef Blog, Reef Aquarium Guides, Coral Care Guides, Identification and Solutions for Pests and Algae, and Reef Dosing Calculators, in addition to the original Reef Parameter Log.

Reef Stable continues to grow, striving to provide a single location for all your reef tank needs!

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