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


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. These are the steps and medications that we use to quickly get our fish to health.

Step 1: Do Your Quarantine Tanks Have You Got One?

A quarantine tank is an aquarium that contains only new fish. This allows you to ensure that your fish are healthy and won’t infect other fish. You may think, “I don’t need a quarantine for my new fish. 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. Therefore, whenever you buy fish or even get them from a friend, don’t immediately put them into your display aquarium. Instead, the best practice is to set up a quarantine aquarium where you can first observe the fish for symptoms and treat them with preventative medications. (This is similar to how we vaccinate new dogs and cats to prevent common disorders from spreading.) This will not only prevent contamination from spreading, but also save money and reduce the risk of losing your life.

This can be a sign that the fish is lethargic. Their chances of quicker recovery are increased if they are kept in a secure environment and 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: Are You Able to Identify the Problem?

Fish keepers, especially beginners, are often unaware of what is ailing their fish. However, it is not productive to ignore the problem. Ideally, we want to treat the issue as soon as possible to give the fish the best chance of surviving. Broad-spectrum medication for fungal, bacterial and parasitic infections is a good idea. However, there are hundreds of medications available all over the world. These medications will provide effective protection for most conditions. They are safe to be used with shrimp, snails and baby fish.

After consulting with ichthyologists as well as spending thousands of dollars in development and 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 harm beneficial bacteria in your tank.

Description of quarantine medication trio

Many people are curious about “I have two of these medications.” It is okay to replace one of these medication with another brand. Unfortunately, some combinations of medications can prove toxic. This is why licensed pharmacists are trained to only prescribe safe and effective drugs. Without thorough testing, we don’t have the ability to determine if other medications will work well together. Additionally, there are many different types of medication that are available on the market, some only in certain countries. We don’t know if these unidentified products are safe for fish, invertebrates and plants.

Step 3: How to Care for Your Fish in Sickness

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. Maracyn or Ich-X may be used if fish fungus is suspected. ParaCleanse is recommended for tapeworms and other parasites. It should be repeated every two to three months to kill any eggs still in the hatching fish.

Trio for quarantine medication

However, if you need to quarantine fish, or if you are unsure about the ailment, all three medications can be used simultaneously. Sometimes, a fish may be suffering from one type of illness. This can lead to an open wound, which could make the fish more susceptible to secondary bacterial infections. It is best to treat all three types to ensure that the fish has the best chance for recovery.

1. If you are treating new fish, make sure the quarantine tank is far away from your normal display tank, and do not let the tanks share any nets, siphons, buckets, or 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. If you are treating the entire display aquarium, do a thorough cleaning of the tank to make sure the fish’s environment is optimal and free of any stress factors before starting treatment. You can inspect the fish’s condition by wiping the aquarium walls. 3. Remove any chemical filtration (such as activated carbon or Purigen), and turn off any UV sterilizers you may be using. Consider adding extra surface agitation (such as with a simple air stone and air pump), since some medications can change the water’s viscosity and hamper with the fish’s breathing ability. 4. Do not follow the instructions on the box. For every 10 gallons, add 1 packet Maracyn and 1 packet ParaCleanse. (Ich-X is not known to stain aquarium decorations. However, it can stain clothes and skin if spilled. 5. For one week, let the fish soak in their medication and then do not feed or change water. (If you feel you must feed your fish, wait until Day 4 or 5, and only feed them very lightly.) During this time, you should leave the heater and aquarium filter on. Also, aquarium lighting will not deactivate the medication. 6. After 1 week has passed, change out 30% of the water in the aquarium. Resume feeding the fish, keep the water quality high, and watch for any change in symptoms.

If you have very weak fish, it may be easier on their bodies to space out the treatment. Bacterial infections tend to be the most common. For a week, use Maracyn at the dose recommended in Step 4. Ich and external parasites are the second most common, so next treat the fish with Ich-X for a week. ParaCleanse should be administered in the third week for gill flukes and internal worms.

If you can clearly identify the illness (such ich), then switch to the appropriate medication and complete the quarantine med triage.

A few days after starting the quarantine treatment, you might notice obvious signs like ich (or white-spot disease) appearing. 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.

You may want to treat all fish in your home, even if they are not familiar with the treatment. You should then be proactive in treating any new fish that come into your home. Although medication can be costly, pathogens can remain dormant for long periods of time waiting to infect your fish’s immune systems. These medications should always be available for emergency situations, based on our own experience. Chances are that you won’t be able to find them last minute at your local pet store and will have to either wait several days to receive an online shipment or settle for an untested brand that may not work at all.


You can play an active role in the health of your fish

We are very passionate about quarantining all new fish, no matter who you get them from, because even changing their environment (e.g., different water parameters or new social hierarchy) can trigger disease. We preventively treat every fish that comes into our fish store. This ensures they are healthy before they leave 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: