How to Treat Sick Aquarium Fish (even if You’re Not Sure What’s Wrong)

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How to Treat Sick Aquarium Fish (Even If You’re Not Sure What’s Wrong)

Treating a sick aquarium fish can be difficult, especially if you’re new to the hobby or have never seen this disease before. We have years of experience in helping customers at the fish shop and online. Here are the steps we follow and the medications we use to bring our fish back to good health as quickly and efficiently as possible.

Step 1: Do you have a Quarantine tank?

A quarantine tank is a smaller, bare tank for the purposes of holding all new fish before adding them into your main display aquarium. This allows you to ensure that your fish are healthy and won’t infect other fish. But you may say, “I don’t need a quarantine tank for my new fish because they all look healthy. It is possible to get sick from fish that have not been ill. This is because although the fish’s original host may have an illness, their strong immune system keeps it under control without any visible symptoms. When you add it to your main aquarium, the host fish may get stressed by its new environment, thus weakening its immunity and allowing the infection to spread to other fish.

It is most likely that fish are brought in by a wholesaler or breeder from fish stores. A place that has many fish in one tank is more likely to have fish diseases. Don’t buy fish from friends or purchase them directly. A quarantine aquarium is a good idea. This will allow you to first examine the fish for signs and then administer preventative medication. This is similar in practice to how we vaccine new cats and dogs to stop common disorders spreading. This prevents contamination and will save you money over the long-term.

These fish are acting lethargic, which is a symptom of many types of disorders. Their chances of faster recovery are increased if they’re treated in a secure, isolated environment that is away from other fish.

A majority of people don’t have a quarantine tank. They’re either new to the hobby and/or think it’s too complicated. But it only takes one severe outbreak to realize the importance of having one. If you have a disease in your aquarium, it is best to treat the whole tank with medication.

Step 2: How can you identify what’s wrong?

Many fish keepers, especially novices, don’t know what has happened to their fish. But, not only is it not productive, but they also may not be aware of the cause. Ideally, we want to treat the issue as soon as possible to give the fish the best chance of surviving. Therefore, we advise covering all your bases by using broad-spectrum medications for bacterial, fungal, and parasitic infections. However, there are hundreds of medications available all over the world. What medications are safe for use with fish, plants, shrimp, snails, baby and sensitive fish without scales?

After consulting with ichthyologists as well as spending tens to thousands of dollars in development and extensive testing, we were able to narrow down our search to three medications, Mardel Maracyn (Aquarium Solutions Ich-X) and Fritz ParaCleanse. We have found that all of these medications are safe to be combined and will not cause any harm to the beneficial bacteria in your tank.

Description for the trio of quarantine medications

A lot of people ask, “I have two out of these three medications. Is it OK to swap one of these medications for another? Unfortunately, certain combinations can be toxic. That is why licensed pharmacists in humans only prescribe medications that are safe together. We don’t know if certain medications are compatible with other fish medications. There are many types of medication available, some of which are not available in all countries. We do not know whether these unknown products will be safe for all fish, invertebrates or plants.

Step 3: How to Treat Your Sick Fish

If you are fairly certain of which disease your fish has, treat for that specific sickness first with the appropriate medication, and follow the instructions on the packaging or manufacturer’s website. For example, if you see fish fungus, read our full article and consider using Maracyn and Ich-X. ParaCleanse can be used to detect tapeworms and other internal parasites. You should also treat the fish every two to three weeks for any eggs that may have hatch.

Trio of quarantine medications

On the other hand, if you are quarantining new fish or you are not certain which ailment you’re dealing with, use all three medications at the same time. Sometimes, a fish may be diagnosed with a specific type of disease, such as fungal. This can lead to an open wound, which could make the fish more susceptible to secondary bacterial infections. Thus, it’s best to treat for all three types of infection to give the fish the greatest chance of recovery.

1. When treating new fish, be sure to keep the quarantine tank away from the main display tank. Do not share your tanks with siphons, buckets, nets, or any other equipment. Since droplets of water can travel on your hands to another aquarium, make sure to thoroughly wash your hands and arms with soap and hot water between tanks. 2. To ensure that your fish are in a healthy environment, you should clean the tank thoroughly before beginning treatment. Clean the aquarium walls to allow you to observe the fish’s condition. 3. Remove any chemical filtration (such as activated carbon or Purigen), and turn off any UV sterilizers you may be using. You might consider adding additional surface agitation, such as with an air stone or pump. Some medications can alter the water’s viscosity which could affect the fish’s breathing ability. 4. Do not follow the instructions on the box. Instead, add 1 packet of Maracyn, 1 packet of ParaCleanse, and 1 U.S. teaspoon of Ich-X for every 10 gallons of aquarium water. (Ich-X does not stain aquarium decorations in our experience, but be careful not to spill it because it can stain your skin or clothing.) 5. Allow the fish to soak in the medication for at least one week. Do not feed or change the water for the next week. You can feed your fish only lightly if you feel that you have to. Wait until Day 4 or 5. You should keep the aquarium filter and heater on during this time. Also, aquarium lighting will not deactivate the medication. 6. After one week passes, change out 30% water in your aquarium. Keep the fish hydrated and keep an eye on any symptoms.

It may be easier for fish with weak bodies to spread out treatment. Bacterial infections are the most common, so use Maracyn first for a week (at the dosage recommended in Step 4). External parasites and Ich are the most common. Next, treat the fish with IchX for a week. Internal worms and gill flukes are slower-acting pathogens, so dose ParaCleanse in the third week.

If it is possible to identify the illness (such like ich), you should switch to the right medication and complete the remainder of the quarantine medicine trio.

A few days after starting the quarantine treatment, you might notice obvious signs like ich (or white-spot disease). Follow the manufacturer’s instructions to determine the right medication for you (e.g. Ich-X). After the ich has been beaten, give the fish some time to rest and then treat the fish with ParaCleanse and Maracyn for 1 week, as suggested.

Consider treating all your fish, even if you’ve never done so before. Then proactively treat all new fish that enter your home so that nothing slips through. Yes, medication can be expensive, but pathogens can lie dormant for a long time, waiting for the chance to take over your fish’s immune system if they get stressed or we lapse on tank maintenance. We recommend that you always have these medications available in an emergency. This is based on our personal experience. It’s likely that you won’t find these medications in your local pet shop. Instead, you will need to wait several weeks to order online. Or settle for a less-tested brand that may not work.

Play an active role in your fish’s health

We are passionate about quarantining any new fish, regardless of where they come from. Changes in their environment, such as new water parameters or social hierarchy, can cause disease. That’s why we preventively medicate every single fish that enters our fish store and ensure they have a clean bill of health before leaving our care.

In the same way, take the proper precautions to ensure your own fish can lead long and healthy lives.

Are you dealing with a specific sickness in your aquarium fish? Check out our list of articles with detailed instructions to help you: