The uncomplicated quarantine tank guide for beginnersHave you been arguing with yourself about keeping a quarantine tank? Don’t worry; you’re not alone in that. Aquarists scouring the internet to learn more about the topic will run into conflicting opinions.

The truth is, there’s no denying the importance of a quarantine tank (QT). Be it saltwater or freshwater fish, a QT can potentially help you save the lives of your fish plus wads of cash. Stay with us as we highlight all things quarantine tank-related, including how to quarantine saltwater fish successfully.

What Is a Quarantine Tank?

A quarantine tank is an independent aquarium used to house newly acquired or diseased fish (or other life forms). Sometimes referred to as a hospital tank, it provides a place for the fish to recover until they’re disease-free and ready to join the fish community in the main aquarium.

What Is the Purpose of a Quarantine Tank?

We’ve already briefly explained what a quarantine tank is. Now, let’s focus on the purpose of an emergency quarantine tank.

Many freshwater fish keepers aren’t big fans of a QT because it’s generally viewed as a waste of money, they’re right, to an extent. You see, most freshwater fish are commercially bred, which means there’s little chance of disease, infection, or parasites from outside sources.

However, there’s no such thing as a 100 percent guarantee that the freshwater fish you bring in from your local aquarium is going to be completely healthy.

– Acquiring Natural Habitats

Besides that, when it comes to saltwater fishes, they’re almost always acquired from their natural habitats. That’s because breeding most saltwater fish species in captivity isn’t too successful. That means the fishes you’re bringing in from the aquarium have a considerable chance of being diseased or infected with parasites.

Imagine accidentally introducing a diseased fish into an established aquarium. You’re endangering all your healthy fishes and running the risk of them falling ill or even dying. That’s not bearing in mind all that extra costs related to medications or trips to aquatic vets.

We’re pretty sure the saying ‘better safe than sorry’ was made for occasions such as this. In short, a reef quarantine tank (or any other kind) can help you dodge a significant disaster by providing you and the life form you plan to introduce to the main tank with accommodation for a relaxing recovery period.

– Backup Quarantine Tanks

Aside from all that, having a backup quarantine tank for fish can come in super handy when one of your finned friends comes down with an infectious illness.

It allows you to move the infected fish to a safe environment for treatment and keep all the healthy tank inhabitants from falling ill at the same time. What’s not to like about that?

How To Set Up a Quarantine Tank?

We’re hoping by this point, you’re convinced of the practicality and usefulness of a quarantine aquarium. If yes, this next section is an absolute must-read for aquarists hoping to set their own hospital tanks.

– Essential Equipment for a Saltwater Quarantine Tank

Before we get down to the basics of setting up a saltwater QT, you’ll need a quick rundown of the essential equipment required. Here’s what you’ll need:

– Aquarium

Quarantine tanks require an aquarium; where the fish(es) go. Experts suggest saltwater isolation tanks can range between 20 to 40 gallons.

However, you may need to make adjustments depending on the type of fish you keep. For instance, if you’re a nano-fish type of person, you can get by with a 10-gallon tank. If you’re a fan of large fish, you may need to bump up the measurements to 50 to 60 gallons.

– Filter

You’ll need to equip your QT with an effective filter to keep toxic compounds and water quality under control. You can opt for internal or hang-on-the-back filters.

It’s also best to have cycled bio-media for the filter because it’ll help the QT build up beneficial bacteria faster to break down the ammonia.

– Lighting

Unless you’re trying to quarantine plants with high light exposure, a small LED light will work just fine for your QT.

– Heater

Another essential component of an isolation tank is a heater. You’ll need a top-notch heater to achieve the required water temperature. Be sure to buy a heater in correspondence with your tank size because if the heater turns out to be too big or small, it’ll cause water temperature issues.

– Siphon

A siphon or gravel vacuum will go a long way in making the necessary water changes more manageable.

– PVC Pipe

Aquarists who favor creating a quarantine tank will breathe a sigh of relief to learn they won’t need to make unnecessary investments. If you want your QT to have some decor while providing shelter for the fish(es), you can always add PVC pipes measuring three to four inches in diameter.

– Other Essentials

An isolation tank should also feature a mesh lid to keep the inhabitants from making an escape. Besides that, it’s also wise to have water and copper testing kits, appropriate medications (confer a vet or an expert aquarist), a refractometer, and a thermometer handy to be able to monitor water conditions.

Steps to Set up

Before setting out the steps to setting up a quarantine tank, here are a few pointers fish keepers should heed. You’ll need to keep in mind fish behavior and how they interact with each other, even in the isolation tank.

For instance, if there’s more than one fish in the QT, you don’t want to mix the aggressive kind with the peaceful ones.

Also, don’t be tempted to add substrate, plants, or elaborate decorations to the QT. Doing so will increase your effort to maintain water parameters and keep the tank free of debris. Now that we have that out of the way let’s move to the steps you’ll need to take to set up an isolation tank successfully.

– Step 1

When you’ve brought your newly acquired fish home, practice drip acclimation to introduce the fish to the QT slowly. To do this, float the fish bag in the QT to equalize water temperature. Next, empty the fish bags into a bucket that allows the fish to stay fully submerged in the water from the bag.

Now you can start transferring the water from the QT in the bucket. You can opt to transfer the water manually with the help of a (small) cup or purchase a drip acclimation kit. If you’re opting manual method, you’ll have to transfer half a cup of water from the QT in the tank every five minutes.

– Step 2

Once the volume of the water in the bucket has doubled, remove half of it with the cup or siphon tube and dispose of it. Proceed to fill the bucket (as before) to double the volume again. Now your fish is ready to be transferred to the QT.

It’s best to move the fish to the QT without adding any water from the bucket; that’s why it’s best to use your hands, a cup, or a net to make the switch.

– Step 3

After adding your fish to the QT, it’s best to keep the lights around the tank dim for a few hours. Doing so will help the fish relax and get used to its new environment.

Now that your fish is safely in the isolation tank, your first order of business is to figure out if it’s sick and the sickness it’s suffering from. You’ll have to keep a close eye on it and closely observe it every day for at least three to four weeks.

Once four weeks are up, and your fish appears none the worse for wear, you can think about moving it to your display tank.

– Step 4

While you’re awaiting the four-week quarantine period to run out, you’ll have to be diligent about maintaining water quality. Remember, fish waste contains ammonia, and ammonia toxicity can be deadly for fish. That’s why it’s best to monitor the QT for ammonia on a daily basis. Anything above zero ppm (even if it’s 0.2ppm) should prompt a 50 percent water change to get the ammonia levels back to normal.

Additionally, keep ammonia detoxifiers handy to control ammonium to ammonia conversion after a water change due to pH fluctuations.

– Step 5

If you’ve figured out what’s ailing your fish, you can either refer to an expert aquarist for over-the-counter medications or refer to a qualified aquatic vet (if you feel the occasion calls for it).

Once you have the appropriate medication, start treating your fish according to the instructions and complete the whole course, no matter the time frame.

Once your fish has been treated with the medication for the entire course, wait for the quarantine period to end before you start to think about adding it back to the main aquarium.

Medication can sometimes take away apparent symptoms (such as white spots) even before the pathogens are entirely cleared for your fish’s body. In short, wait out the whole isolation period before switching the fish to the main tank.

Once four weeks are up, and your fish appears completely fine, you can shift to the display tank via drip acclimation. Follow the steps listed above and allow your fish the time to get used to the main tank’s water. It’s an essential step to keep your fish from getting stressed.


Quarantine tankHaving a quarantine tank at the ready can help you save the lives of your fishes and save lots of money simultaneously. Here’s a quick rundown of what the procedure requires:

  • The first piece of equipment required to set up a QT is an aquarium. Anything with a tank capacity between 20 to 40 gallons should suit fine. If you’re a nano-aquarist, a 10-gallon tank will suffice. Fish keepers with sizeable fish can stretch tank capacity to 50 to 60 gallons as needed.
  • An isolation tank will also require an effective filter to maintain water quality. You can opt for internal or hang-on-the-back filters with cycled bio-media because it’ll help the QT build up beneficial bacteria faster to break down the ammonia.
  • Isolating a new fish will require aquarists to practice drip acclimation to smoothen the transfer process. Fish keepers can opt for a small LED for lighting purposes.
  • You’ll also need to set up a heater for your isolation tank to control water temperature, along with a siphon (to clear debris from the substrate) and a PVC pipe to provide the fish shelter.
  • An isolation tank should also feature a mesh lid to keep the inhabitants from making an escape. It’s also wise to have water and copper testing kits, a refractometer, and a thermometer.

Having learned what you need for a QT and how to set it up, it’s time for you to get yourself in gear and have an isolation tank prepped if there’s a need for it. It’s quickly done and can help you practice prevention to avert tragedy.

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