When to Quarantine Betta Fish (and How to Do It Right)
Aquarists set up quarantine tanks for two reasons: to treat a sick fish or to observe a new one for any signs of disease before introducing it to a community tank. But for many beginners, it’s pointless to quarantine a single betta fish that’s destined for a glass bowl or a flower vase.
Sadly, this mindset leads to grave mistakes and unnecessary suffering for the fish. While Siamese fighting fish are indeed resilient, we must understand that even these hardy fish benefit from a proper quarantine setup.
It doesn’t really matter whether your betta will live alone or join a community. So if you’re thinking of getting one, first you’ll need to learn why quarantine matters and how to quarantine betta fish the right way.
When Should I Quarantine a Betta Fish?
Aquatic vets strongly recommend isolating any newly bought fish. And yes, that includes active, seemingly healthy bettas that you just bought from a local pet store or an online fish retailer. From there, your fish’s next stop should be the quarantine tank.
Quarantine Your Betta Right After Bringing It Home
Your Siamese fighting fish might be fighting off parasites or infections that aren’t showing symptoms yet. It’s actually quite common for bettas to get sick within the first week.
A sudden change of environment causes a lot of stress for your fish, consequently weakening its immune system. By isolating your betta fish temporarily, you’ll be able to spot issues early on and treat them more effectively.
But if you immediately add your betta to a community tank, even a common condition like Ich becomes a nightmare to deal with because some fish species are more sensitive to medication. Treatment gets even trickier if you have live plants.
Even if your betta won’t be sharing the tank with any other fish, you still want to set up a betta quarantine tank. Otherwise, your fish might introduce parasites into the decor, filter, and substrate of the main tank.
Quarantine Your Betta When There’s Sudden Physical or Behavioral Changes
Now, if you’ve done that and had your betta fish for a while, you’ll want to keep an eye out for the following signs, as they could mean your betta needs to be moved back into quarantine for treatment.
Signs a betta fish needs to be quarantined:
- White spots, rapid breathing, frequent rubbing against decorations (Ich)
- Faded color, loss of appetite, clamped fins (Velvet)
- Ragged fins (Fin Rot)
- Lethargy, gulping for air, red gills (Ammonia Burn)
How to Set Up a Betta Quarantine Tank
A betta fish quarantine tank setup only needs a few key essentials to be effective. It doesn’t need to be as decorative or elaborate as your main tank. Here’s how to set it up.
Fill a 5-Gallon Aquarium with Conditioned Water
A good quarantine tank size for betta fish is 5 gallons. With this volume, it’s much easier to maintain stable water conditions and accurately dose medications. If you use tap water, dechlorinate and detoxify it first using Seachem Prime or any other high-quality water conditioner.
Then install a 20-watt submersible heater along with a reliable thermometer. Aim for 76–81°F, ideally leaning toward the upper range to keep your little tropical fish as comfortable as possible.
Using a liquid test kit, you’ll want to test your water parameters before adding your betta. Be sure to maintain the recommended parameters, especially if your fish has already fallen ill. Sick bettas are much more vulnerable to toxins like ammonia and nitrite.
| Parameter | Ideal Value | Frequency |
|---|---|---|
| Ammonia | 0 ppm | Daily |
| Nitrite | 0 ppm | Daily |
| Nitrate | < 20 ppm | Every 2-3 days |
| pH | 6.5-7.5 (stable) | Every few days |
Install a Sponge Filter and an Airstone
Whoever said bettas are “hardy enough” to survive without filtration or aeration clearly never loved a pet fish! Even in a temporary setup, you should install a low-flow filter and an aerator to improve oxygen exchange and water circulation. A small sponge filter and a bubble stone make an excellent pair because they don’t create strong currents that could stress your fish.
Add a Few Hiding Spots
Give your betta fish shelter using smooth items that are easy to wash or replace, such as terracotta pots, PVC tubes, and smooth river rocks. You can also add duckweed and hornwort for a natural touch. After the quarantine period, safely dispose of or disinfect the decorations before reusing them.
Common Mistakes When You Quarantine Betta Fish
Setting up your betta quarantine tank is just the first step. Knowing what to do (and what not to do) once your fish is in is equally important.
You Don’t Change the Water or Check the Parameters Regularly
Cycling a betta quarantine tank isn’t necessary, especially if you keep up with the Seachem Prime every 48 hours. Even so, it’s always a good idea to do a 10% water change every day to maintain water quality. And if you’re using medications that cloud the water, you’ll want to check your parameters more frequently, as these meds can cause ammonia levels to rise rapidly.
You Use Substrates
No gravel, sand, or fancy substrates, please. A squeaky clean bare-bottom setup is ideal for quarantine or hospital tanks because you can easily siphon uneaten food, fish waste, and other debris.
You Overfeed Your Betta
Uneaten bits of food quickly pollute the water, which is especially dangerous in a small, uncycled tank. That said, it’s best to keep feedings light and consistent, with one small meal per day that your betta can finish in 1-2 minutes.
If your fish is in quarantine and being treated, keep in mind that some medications can suppress appetite, so don’t panic if your betta doesn’t eat much.
You Transfer Your Fish Too Early
Two weeks is the standard quarantine period for new fish, but ask any seasoned aquarist and they’ll say go for four. That’s because diseases like Mycobacteriosis (Fish TB) and Lymphocystis (a viral infection) take their sweet time to show.
So if you’re going to introduce your betta fish to a community tank, it’s wise to stretch the quarantine period to four weeks. Better safe than sorry!
Final Words
Setting up a quarantine tank for your betta fish allows for early detection of diseases and ensures a smooth transition into its new home. If you enjoyed this guide and want to keep learning more about betta care, we warmly invite you to subscribe to our newsletter for valuable tips and insights!