Setting up a quarantine tank is easy, too easy.  You don't need expensive or fancy equipment and you can use just about any old aquarium. Whether it's a used tank, something from your local fish store, or a nice rimless AquaMaxx tank like Matt used in the video, it does not matter.  The tank just needs to hold water and support a few pieces of equipment. It can be glass or acrylic, you just need to be able to see and observe your fish closely so avoid something with scratches or damaged viewing panes. 

Matt's Quarantine Tank Shopping List

Quarantine tanks are unique in that they are simply holding tanks and provide a safe place to observe and medicate fish.  Technically speaking, they will not be cycled aquariums either.  That said, it's a good idea to grab some biological filter media from your display tank and place it into your QT to ensure you have some biofiltration available. Otherwise, you can just do larger (daily) water changes or use ammonia detoxifier additives to eliminate the ammonia your fish produce.

Sponge filters are also another option for a QT but those must be given the appropriate time to cycle and grow nitrifying bacteria.  In this instance, you can store the clean sponge filter in your sump or display tank, allow it to establish beneficial bacteria, then bring the sponge filter into your QT tank when necessary. 

Before adding fish to a freshly set up QT tank, be sure to let the water clear up and oxygenate thoroughly. Check and adjust temperature, salinity, and pH so as not to cause any additional shock stress on the animals. Always use chlorine detoxifying water conditioners or RO/DI water.

It's a good idea to have an ammonia detoxifier, like Seachem Prime, on hand at all times just in case ammonia shows up. The Seachem Ammonia Alert badge is the most practical ammonia indicator for your QT tank and really should be used 100% of the time for safety measures. 

Fish are most often observed for the first 1-2 weeks in a QT without medication. If a problem is observed, you can then treat it with specific medication that will target that problem. Alternatively, you can proactively medicate ALL your new fish which some hobbyists see as the safest approach. 

Medications For Your QT

There is a wide variety of medications you can use in a QT tank.  In most cases, you will never mix medications but some concoctions are safe.  Do the appropriate research to find the best suitable treatments for whatever ailment you're dealing with.

Only with experience will you be able to identify every possible disease, and still your guessing without the appropriate scientific evidence. That means choosing the right medication can be difficult and broad-spectrum treatments are the most common approach. Good news, these medications can tackle 90% of the most common issues a home aquarist will encounter. So you just need to learn how/when to use them.    

  • Hikari Prazi-Pro: Anti-parasitic praziquantel medication to treat flukes, tapeworms, flatworms, and turbellarians that is safe for use in combination with copper. Reef safe, biofilter safe.
  • Copper Power or Seachem Cuprimine, and Fritz Coppersafe: Classic "copper treatment" for external parasites like Ich and Velvet. Reef safe, biofilter safe.
  • Maracyn-Two: Minocycline based anti-bacterial treatment for fin/tail rot, skin infections, red gills or heavy breathing (gill disease), and popeye. Reef Safe.
  • Fritz Maracyn Oxy: Sodium Chlorite based anti-fungal treatment for true fungal infections that result from certain diseases and wounds. Safe for use in combination with Maracyn-Two.
  • Seachem Metroplex: Metronidazole based broad-spectrum treatment for both bacterial infections and external parasites. Biofilter safe.
  • Seachem Focus: Kanamycin sulfate based medication to be mixed with food and targets internal bacterial infections.

10 Most Frequently Asked Quarantine Tank Questions

Can I use reef rock in a QT?

It's generally not recommended because aragonite-based rock can absorb medications and harbor disease-causing pathogens. This makes it difficult to keep the tank sterile in between fish additions and the rock will leach medications for an undetermined amount of time after treatment.  While the benefit of biological filtration the rock can provide is valuable, it's just not the best practice.  That being said, if you're not using medications in the QT tank, reef rock is perfectly safe.

Should I use sand in a QT?

Sand is permitted for animals that need it, but you should isolate it for easy removal. It's best to not just fill your QT with sand for the sake of keeping things clean and avoiding places for parasites and nasty critters to hide/reproduce.  If you have a wrasse, snail, or some other animal that requires a sand bed, just use a Tupperware or similar container filled with sand in the corner of the tank. This way you can easily remove the sand when you're done with it.

Do I need to QT inverts?

Most fish diseases cannot infect invertebrates directly, but it is possible to transfer those diseases via the water inside their shells or bodies. That said, corals can benefit from isolation and coral dips to avoid the transfer of coral pests. Snails, crabs, and other inverts can go through a "tank transfer method" where you temporarily house/dip them in a bucket of water from your display, in hopes of flushing out any risky water before going into your display directly. You can certainly isolate these inverts for 30-90 days as well, you just have to be sure and feed them...QT tanks usually won't have enough algae and microorganisms to keep snails and clean-up crew critters alive.  Also, COPPER IS TOXIC TO INVERTS so be sure you don't expose corals or clean-up crew animals to copper leftover in your QT if you use the same tank.

How do I QT burrowing fish that need sand?

Just fill a Tupperware or small container with sand and put it into the QT. When you are done, discard the sand as it could be contaminated with pathogens or medications. 

Should I preventively treat new fish?  

This is up to you, some hobbyists do but most do not. Proactive treatments can be super stressful and if the fish does not need treatment, why expose it to the stress? Most common approach is to isolate for 30-90 days, treat only those problems you observe. Furthermore, it's difficult to treat for everything without an extensive and stressful routine. 

How do I know which medication to use?

The only way to know for sure is to be able to successfully identify the disease. This is not easy and, of course, is something you learn with experience. So as a beginner, this can be quite difficult but don't let that stop you from trying and gaining that experience for yourself. Reference the product packages and the plethora of information online (articles like this one) to help familiarize yourself with available meds and common techniques.

What does "reef safe" mean?

In the world of QT and medications, "reef safe" means the chemicals in the medication are not directly toxic to invertebrates (corals, snails, crabs, shrimp, etc.). Invertebrates like this are generally only found in reef aquariums.

What does "biofilter safe" mean?

In the world of QT and medications, "biofilter safe" means the medication will not harm your beneficial bacteria. Anti-bacterial medications are common and some of these can harm beneficial bacteria. There are, however, mild anti-bacterial medications that are safe for use with beneficial bacteria, you just have to do the research.  

Do I need to cycle my QT?

No, you don't need to cycle the QT if you are prepared to do frequent water changes and dose ammonia detoxifiers. There is sort of two approaches to a QT, you either cycle the tank using biological filter media, or you don't cycle the tank and just do large water changes to remove and dilute ammonia.  Should ammonia show up, you can use ammonia detoxifying additives like Seachem Prime to immediately make it safe for your fish inside the QT tank.  This is a somewhat debated topic in the world of QT, both approaches work.  

Think of it this way, if you have the time to let biological filter media safely establish in your display tank before getting new fish, that approach works great and saves you the hassle of daily water changes.  If you need to set up and QT your new fish on the same day, you're going to be forced into daily water changes and using ammonia detoxifiers. If you plan ahead, using cycled media is great.  If you buy a fish on impulse without any cycled media that is ready for the QT... well then you're looking at daily water changes.

Do I need to separate maintenance equipment used on my QT tank?

In an ideal world, yes! You should never let fishnets, siphons, scrapers, containers, and other equipment used in your QT be used on your display aquarium; if it gets wet there is an inherent risk of transferring pathogens. That said, you can sterilize your equipment in between uses which is the most realistic approach. Most of us are just not going to buy two complete sets of maintenance equipment just for the initial QT process.

Soak equipment in a bleach-water solution and then rinse it well for immediate sterilization.  Alternatively, you can use a bucket of pure RO/DI water and soak the gear for at least 72 hours. The idea is that freshwater will eventually kill off the saltwater pathogens and drastically reduce the risk of transfer contamination. Letting the gear completely dry out for a few days will also help in some scenarios but again, is still not 100% effective.