Step-by-step how-to

How to set up a quarantine tank for new fish

Step-by-step guide to setting up a fish quarantine tank. Sized, equipped, mature, ready to receive new fish for 21-30 day observation + treatment.

Beginner8 steps14 days

What you'll need

Step-by-step

Step 1: Position the tankIn a low-traffic, dim-lit area. QT fish are stressed; bright light + foot traffic adds stress. Cover with a black background to hide the room.
Step 2: Install filtrationSponge filter only - never carbon (binds copper if treating). Cycle the sponge filter in your display tank for 4-6 weeks before bringing it to QT, OR seed with a handful of established media on day 1.
Step 3: Add hardscapeA few PVC fittings or a small cave for hiding. NO sand, NO live rock, NO porous decor - copper or medications absorb into porous materials.
Step 4: Fill with parameter-matched waterMatch display tank salinity (saltwater) or pH/GH (freshwater) within 2%. Use the same source water (RODI + same salt brand).
Step 5: Cycle if neededIf the sponge filter is uncycled, dose ammonia to 2 ppm + add bottled bacteria. Wait 14 days for cycle to complete before adding fish.
Step 6: Add the fishDrip acclimate for 60-90 minutes. Net into QT - never pour shipping water. Lights low for first 24 hours.
Step 7: Treat prophylacticallySaltwater: copper at 0.35-0.5 ppm OR Tank Transfer Method for 21-30 days. Freshwater: observation only, treat if symptoms appear.
Step 8: Move to displayAfter 21-30 days symptom-free + appetite normal + active, move to display via drip acclimation.

Frequently asked questions

How long should fish stay in quarantine?

Saltwater: 21-30 days minimum with prophylactic copper. Freshwater: 14-21 days observation. Long enough that ich + velvet life cycles complete and can be detected.

Can I keep multiple fish in QT?

Yes if compatible. New arrivals from the same shipment are fine. Mixing arrivals from different sources defeats the purpose.

Do I need a QT for invertebrates and coral?

Coral: yes, 30-day quarantine + dipping protocol prevents AEFW, red bugs, flatworms. Invertebrates: less critical but still recommended for 1-2 weeks observation.

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