How to Treat New Fish in Quarantine (How to Medicate)

How to Treat New Fish in Quarantine (How to Medicate)

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Do you want to know why a new fish quarantine tank could end up saving you a lot of money?

Well, you came to the right place!

A fish keeping fact is that even the most reputable retailer has no control over what the fish they bring in is exposed to. Most of them (sellers) get their livestock from all over the world with no way of telling whether the animals are clean.

I know some shops quarantine their fish, but they are at best few and in-between. Many don’t have space or facilities to isolate new fish, a task that they instead leave for fish keepers (like you) to implement.

Even fish coming from a reputable source with known quarantine protocols need to be quarantined because they are stressed during bagging and transport, which makes them susceptible to disease and infections upon arrival.

So, assuming you do not have a local shop that quarantines their fish, how do you ensure the fish you buy are safe and are not going to infect your whole tank with something.

Personally, I run a quarantine tank for at least 2 weeks (3 is optimal), managing the fish every 24 to 48 hours with pre-treatments that include regiments for external and internal parasites (such as Ick), flukes, bacterial, and even fungal infections.

The main products I use are Api General Cure and Ick X to target Ick, which is notably present in many tropical fishes.

Seachem Kanaplex is ideal for bacterial infections pretreatment, though Erythromycin, Tetracycline, and Melafix are efficient remedies as well.

Also, keep some aquarium salt around in case you need it, even though you might end up not using any.

See more insight below.

How Many Days Should You Quarantine New Fish

When buying fish from a reputable local seller, especially when they are hardy species, quarantine is not a must.

But in most cases, hobbyists get their fish from multiple sources and at varying times. As such, quarantine is necessary since the animals don’t all share the same microecology of parasites and bacterial elements.

I recommend quarantining new fish for between 2 and 4 weeks. During this time, you should also treat any ailments and parasites either with natural remedies or with copper-based medication.

The treatment should last between 14 and 21 days while conditioning your water and doing regular 10 to 15 percent changes.

A 20 to 30-gallon tank makes an excellent quarantine tank and is perfect for more freshwater application. However, a slightly larger or smaller tank will work as well, depending on the number and size of fish you have.

Your quarantine tank need not be too complicated. All you require is some form of lighting, heating, a few plants, and decorations for cover and filtration.

A sponge filter is quite often an ideal choice.

A substrate is not too necessary unless you really want to add it to your aquarium.

How to Quarantine Your New Fish

There are several ways to quarantine new fish, but the basics remain pretty much standard.

Usually, the step is to isolate your new fish in a quarantine tank with water parameters akin to those in the aquarium you plan to add it to.

Since smaller tanks are a catalyst to parasitic attacks and ailments, you will also want to ensure the one you decide to use is adequate for your new individual(s).

As I mentioned above, you’ll also need to add some basic equipment to your quarantine aquarium.

Most importantly, add a filter (preferably sponge) that’s well colonized by bacteria families, enough to clean the bioload of your new fish. It’s easier to pull old media off an old filter in your display tank to help the colonies establish faster.

Some common ornamental fish like goldfish, danios, and white cloud minnow will do fine in a quarantine tank with no heater, but the vast majority of fishes require one.

The rule of thumb is if they are tropical fish, then a heater is almost unavoidable. Betta, discus, all cichlids, tetras, guppies, and other livebearers, cory catfish, loaches, and many more all require a heater.

The heater size you get should be enough for your quarantine tank, plus sometimes it’s good to go a size higher just to be safe.

Decorations, plants, and caves are not all too necessary, but they are recommended, especially if your new aquatic fish are the shy type, such as some plecos and loaches.

Unless you plan on using your quarantine tank to house your fishes in the long term, adding a substrate is not necessary. A bare-bottom setup will work almost as seamlessly.

How to Treat, Medicate Your New Fish in Quarantine

The parameters in your quarantine aquarium should be identical to those in your main tank. As such, the first step is to craft the temperature and water chemistry to the readings of your main display tank.

The next thing you want to do during the 2 to 4 weeks you keep your fish in quarantine is medicate, though using natural treatment remedies is fine.

Ideally, the medication period should last up to 4 weeks for the most common parasites and bacterial infections in new fish.

Something you will see quite often is things like ick and fin rot, especially in fish with flowy tails such as guppies and betta.

That said, it is won’t always be necessary to medicate your fish. If by the first (maybe the second week) they have not shown any signs of ailment, you only need to make sure the tank is clean and safe for them.

Feed your new fish their preferred diet and perform 10 to 15 percent water changes weekly.

Should you decide to medicate your fish (most fish keepers do), I recommend using all-around bacterial and parasitic preventative (antibiotic) treatment while not targeting a specific condition. Just note that any medication given to aquatic animals can be stressful if not administered properly.

In case of ick please see this article and this article if dealing with fin rot, more so in fish with flowy fins like betta, guppies and fancy goldfish.

Essentially, regiments like API general cure will treat external and internal parasites and fluke. so will seachem metroplex.

ICH X is an ideal treatment when trying to treat ich on your new fish. A few drops per gallon should be enough, plus there are directions on most bottles or packaging in case you need some guidance.

Fungal infections are also common in new fish, so you may want to treat for that too.

Lastly, for bacterial infections, most are treatable with antibiotics such as erythromycin, which should not be too hard to find either online or your local fish store.

How to Quarantine Fish Without A Tank (In Bowl, Bucket)

It’s recommended to use a fish tank to quarantine your fish. But you can replace the traditional rows of glass aquarium with economical clear, round 1 to 5 gallons polycarbonate buckets with lids.

Of course, you can also quarantine a small to medium-sized fish in a glass bowl. Just note that both methods are safer when it’s a single (maybe two) fishes that need treatment.

Plus, the process is quite often labor-intensive because you need to do more water changes (30 to 35 percent) and cleaning to keep the bucket or bowl safe.

Glass bowls and polycarbonate buckets are best since they are durable and can be subjected to high heat.

Make sure in the bucket or bowl you can add a heater, thermometer, a few plants, a sponge filter, and any medication if necessary.

Thats all!

Happy fish 🦐🐠 keeping.

Eddie Waithaka

Resident Content Creator and Marketer at AquariaWise who talks about aquariums and fish and aquascapes a lot.

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