Do Beginners Need a Quarantine Tank?

A quarantine tank is a second small aquarium — often 10 to 20 gallons — where new fish spend two to four weeks before joining the display. It catches ich, velvet, and bacterial infections before they infect every fish you own.

You need a sponge filter or cycled media, a heater, and a cover. Treat or observe fish without dosing the main tank. It is extra work, but one outbreak in a 55-gallon community tank costs more in fish and medication than a basic QT setup.

If you cannot run a permanent QT, at least buy from reputable stores and never add six new fish on the same day. Record quarantine start and end dates in ReefDiary livestock notes.