Quarantine sounds like something only serious breeders do, but it’s one of the highest impact habits for any guppy keeper. Many problems enter tanks through new fish: parasites, bacterial issues, or just stress that triggers illness after introduction. A quarantine tank doesn’t have to be fancy. In fact, the simpler it is, the more likely you’ll actually use it. The goal is not “perfect hospital gear.” The goal is a stable, separate space where you can observe and stabilise new arrivals before mixing them with your main tank.
The simplest quarantine setup
- a small tank or tub (even modest size is fine)
- a cycled sponge filter (or seeded media)
- a heater (optional but helpful for stability)
- bare bottom for easy observation and cleaning
How long to quarantine?
A short observation period catches most issues. Watch appetite, posture, breathing, and fins. Healthy fish should settle and feed consistently.
What quarantine prevents
- introducing low-level parasites into a stable display tank
- stressing the whole community with new-fish instability
- treating the main tank unnecessarily with medications
Make it easy to use
Keep the quarantine sponge filter cycled by running it in a main tank when not in use. That way it’s ready when you need it. Quarantine only works if you actually do it.
A simple quarantine habit saves money, saves fish, and keeps your main tank stable. It’s one of the best “low effort, high reward” upgrades you can make.
