How to Acclimate Corals, Invertebrates & Saltwater Fish

Shipping is stressful for any living animal, and proper acclimation is the most important thing you can do for new livestock. Corals, invertebrates, and fish each need a different approach.

Before your order arrives

  • Check that your tank's salinity, temperature, and other parameters are stable.
  • Have airline tubing, a clean bucket, and a net or cup ready.
  • Plan to be home on delivery day so the package doesn't sit outside.

Corals

Corals are sensitive to temperature and light changes but do not need drip acclimation.

  1. Open the shipment in a dimly lit room and turn off your aquarium light.
  2. Float the sealed bags in the aquarium for 15 to 20 minutes to equalize temperature.
  3. If desired, perform a coral dip following the product's directions. Rinse corals with clean saltwater from your tank before placing them.
  4. Place corals low in the tank and gradually move them to their preferred light and flow over several days to prevent stress or bleaching.

Invertebrates

Invertebrates are more sensitive to salinity and parameter swings than corals, so drip acclimation is recommended.

  1. Open the shipment in a dimly lit room and turn off your aquarium light.
  2. Float the sealed bags for 15 to 20 minutes to equalize temperature.
  3. Open the bag and drip acclimate with airline tubing at 2 to 4 drops per second for 30 to 60 minutes, or up to 90 minutes for delicate species.
  4. Gently transfer the inverts into your tank with a net or cup. Don't add bag water. Keep lights low for the first few hours.

Fish

Fish produce waste that lowers pH during shipping. Once the bag is opened, pH rises and that waste (ammonia) becomes toxic, so do not drip acclimate shipped fish.

  1. Open the shipment in a dimly lit room and turn off your aquarium light.
  2. Float the sealed bags for 15 to 20 minutes to equalize temperature.
  3. Open the bag and immediately transfer the fish into your tank with a net or cup. Don't add bag water. Keep lights low for the first few hours.

What's normal for new arrivals

  • Corals may stay closed or retracted for several days before fully extending. Be patient.
  • Invertebrates are often nocturnal and may not move much at first. Activity usually picks up at night.
  • Fish may hide or refuse food for the first 1 to 3 days.

If something looks wrong on arrival

  • The bag feels very cold or very warm: float it longer, 30 minutes or more, so the temperature changes slowly instead of all at once.
  • A coral is shriveled or covered in slime: this is a common stress response to shipping. Acclimate as normal, place it in low light and gentle flow, and give it a few days.
  • A snail or invert isn't moving: many are slow to respond after shipping. Acclimate as normal and check again after lights out. A strong, foul smell is the clearest sign a snail has died.
  • Something arrives dead: take clear photos in the original, unopened bag within two hours of delivery and contact us. See our refund policy for details.

Please note

  • Macroalgae, gorgonians, and sponges should not be dipped.
  • Gorgonians and sponges should never be exposed to air.
  • We do not recommend using medication with invertebrates.
  • We recommend quarantining all new livestock, regardless of the source.

More guides: coral care, invertebrate care, and macroalgae care.

FAQ

Should I drip acclimate corals?

No. Corals only need to be temperature-acclimated by floating the bag, then optionally dipped before placing them in the tank.

Why shouldn't I drip acclimate fish?

During shipping, fish waste builds up as ammonia, but the low pH in the bag keeps it relatively harmless. Once the bag is opened and pH rises, that ammonia becomes toxic, so fish should go into the tank quickly.

What should I do if something arrives dead?

Take clear photos of the specimen in its original, unopened bag within two hours of delivery and contact us. See our refund policy for full details.

Do I need to quarantine new livestock?

We recommend it for all new livestock, from any source. Quarantine helps keep pests and disease out of your display tank.

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