Easy Marine Quarantine Tank Setup

Have you decided that you want to go ahead and quarantine your marine fish or crabs and shrimp? Good idea! Luckily, a quarantine tank is cheap and easy to set up.

People often quarantine animals and marine fish or reef animals in order to prevent the spread of disease. This is done in many settings, such as zoos and public aquariums, as well as when introducing new fish to your aquarium. It is important to have some sort of quarantine procedure in place to avoid the spread of disease to other fish already in your main tank under your care.

An ideal quarantine tank for fish should be at least 15 gallons in size (56 litres), but this is dependent on what kind of animals you are quarantining, and also your space requirements. For example, for an invert-only quarantine tank, we have used a tiny Pico-style 2-gallon tank without any trouble, but it does require changing the water quite often, maybe every other day. If you have the space, go for a larger tank – the larger the tank, the more stable and forgiving the water parameters, especially in terms of waste accumulation, and the easier the quarantine process will be in maintaining your tank’s water quality. This means you don’t have to change the water as often.

A properly set up quarantine tank with a heater, rocks, and PVC hiding places for the fish

Aside from being a decent size, your quarantine tank should have a hang-on back or internal sponge filter that is already seeded from your main tank. Using used sponge media from an existing tank will help ensure that your quarantine tank has the necessary beneficial bacteria to break down the waste generated by your tank’s inhabitants. Remember: keeping water parameters consistent and in the range is key to the survival of your fish, especially as they are undergoing the stress of being sold and transported to a new home. Make sure you test the water of your quarantine tank frequently.

A small HOB (Hang on Back) filter works great with a quarantine tank. Make sure you add filter floss from an established aquarium

Some people keep a quarantine tank running at all times, however, this is not absolutely necessary; as long as you keep some extra filter media in your main tank you can use it in your “as-needed” quarantine / hospital tank. This way you can create your fully cycled quarantine tank on demand.

Other than the above, your quarantine tank should also have a heater (and/or small chiller if you live in a tropical region) to keep the temperature stable (at somewhere between 24-28 celcius or 75-85 Fahrenheit). Typically a warmer tank will speed up the life cycle of the most common reef or salt water fish parasites. If you prefer a quicker quarantine period, try keeping the tank on the warmer side if possible and within the tolerances of the fish you are treating.

A small clip on LED light should suffice to provide lighting unless you are quarantining corals, which would need more intense lighting. Watch out though for heat dissipation issues if using powerful lights on a smaller quarantine tank, monitor the temperature closely.

An affordable LED lamp like this is all that is needed to quarantine fish, though inf you are quarantining corals, you may want something more powerful.

To keep the stress levels of your new fish to a minimum, you should also provide some PVC piping or a coffee mug to allow your new fish to hide. Make sure you do not keep sand in your tank and are running it bare bottomed. Fish are surprisingly aware of their environments and are typically skittish and scared when they are introduced to your quarantine tank. Should you be quarantining fish that dig or burrow in the substrate (some wrasses or gobies), you should add some silica sand or other non-calcareous substrate (which is more inert) in a small bowl placed in the tank to allow the fish to hide. It is important that you do not use aragonite or other sands as they will absorb medications (particularly copper) making treatment difficult.

Salifert test kits are an affordable testing kit brand - cheap and accurate.

Lastly, ensure that you have the proper test kits (pH, Ammonia, Nitrite Copper, dkH and Nitrate) on hand. Seachem has a handy ammonia alert to let you know when ammonia is at a critical level and a water change is needed. We use Salifert tests, they are the most affordable and the most accurate.

A log will help you develop a regimen to keep your reef parameters in check

Lastly, part of the quarantine process is down to the fishkeeper! Develop good habits early on and you will be more successful in the task of quarantining reef fish – for a quarantine tank, test the water daily or at a minimum once every two days if you have a large quarantine tank, to ensure all parameters are within range. Perform water changes as needed (likely 50% every 2-7 days, depending on the size of your tank), to ensure water parameters are perfect – giving the best chance of survival for your new reef additions.

Now that you have your quarantine tank set up, you need to decide on the duration or how long to quarantine your fish, and what medications (if any) you need to use on your fish. Reasons for quarantining fish are numerous and we discuss them in our post on Why Should You Quarantine Your Fish? Most people will reach the consensus that quarantining your fish is probably a good idea, but the next factor to decide is for how long the quarantine period should be.

Remember a quarantine tank size can be small, if you are only quarantining a few small fish at a time

The duration will depend on what kind of medications you are using and how you are using them, but a quarantine period should be two weeks as a minimum. There are two camps when it comes to the duration of marine or salt water fish quarantine, those on the side who want their fish to be in quarantine for longer to ensure they are disease free, and those who want a shorter quarantine. There are ways to reduce the time that your marine fish need to be quarantined, while also reducing risk of spreading disease to your display tank. Our article on How Long Do I Need to Quarantine my Saltwater Fish? answers this question by taking a look at what should be considered when deciding on quarantine time for reef fish.

Medications that are essential for marine fish quarantine

You will also likely need medications such as Cupramine, Prazipro, Paraguard, and Metroplex for marine fish – it is best to have these on hand before your fish get sick – we have listed out in our article exactly which Medications you will need for Treating Marine Fish Diseases in Quarantine which also goes which medications are needed for specific ailments and how to dose them properly without stressing out or harming your new fish