Quarantining new guppies is one of the most effective habits you can build — and one of the most skipped. The reason people skip it is simple: they think quarantine means a second “full aquarium setup”. It doesn’t. A quarantine tank can be basic and still do its job: protect your main tank and give new fish a low-stress place to settle.
What quarantine is for
- Observation: spot issues early (clamped fins, flashing, appetite changes).
- Stabilisation: allow fish to recover from shipping/relocation stress.
- Protection: prevent parasites or bacterial problems entering an established tank.
The simplest quarantine setup
- Tank: 20–40L is plenty for a small batch.
- Filter: sponge filter (easy and safe).
- Heater: stable 24–26°C.
- Hiding: a small plant clump or PVC elbow so fish feel secure.
- Bare bottom: makes cleaning easy and helps you see waste.
A calm 14-day routine
- Days 1–3: keep lights low, feed lightly, watch behaviour. Test ammonia/nitrite daily.
- Days 4–10: normal feeding, routine observation. Small water changes as needed.
- Days 11–14: confirm fish are stable: eating well, fins open, no flashing or heavy breathing.
Should you medicate automatically?
Not always. Many issues are stress-related and resolve with stable water and oxygen. Blanket medication can create more stress than it prevents. The safest rule is: treat only when you have a target. If you do treat, keep aeration high and follow label directions carefully.
When fish are ready to move
Move fish when they are eating confidently and behaving normally for several days. Transfer them with a net (don’t pour quarantine water into the main tank). If you’re unsure, extend quarantine a week — it’s always cheaper than treating a whole display tank.
A simple quarantine routine saves enormous effort later. It protects your established fish, reduces disease outbreaks, and makes every new addition settle faster and show better colour.
