Reef Beauties Acclimation Guide

How to safely acclimate saltwater fish and invertebrates after overnight shipping

Why Acclimation Matters

Your new arrival has spent 12–24 hours in a sealed shipping bag. During this time, pH drops and ammonia builds up — making proper acclimation essential. Follow the steps below to safely transition your fish or invertebrate into your aquarium while minimizing stress and risk.

Quick Overview

Total time: 30–60 minutes

What you need:

• Clean bucket or container
• Measuring cup or turkey baster
• (if possible) Ammonia neutralizer (e.g., Seachem Prime or Fritz Complete)
• Net

Important: Keep aquarium lights off during and after acclimation

Step-by-Step Acclimation Instructions

Step 1: Turn Off Aquarium Lights

Turn off all lights before you begin and keep them off for 4 to 6 hours after introducing your livestock. They have spent many hours in the dark box, so the sudden light can be shocking to them. This helps reduce stress and aggression from tankmates.

Step 2: Float the Sealed Bag (Temperature Matching Only)

Float the unopened shipping bag in your aquarium or sump for no more than 10 to 15 minutes to equalize temperature. Do not open the bag at this stage. Floating longer than 10-15 mins can allow ammonia to build and accelerate toxicity. Your livestock will continue to temp acclimate in the ensuing steps.

Step 3: Open the Bag and Add Ammonia Neutralizer

After floating, open the bag away from the tank and pour the fish and bag water into a clean container. Immediately add a few drops of ammonia neutralizer (such as Seachem Prime) to detoxify any harmful ammonia.

Important Note on Salinity

Our fish are shipped in water with a salinity of 1.018–1.019. This helps reduce stress and eliminate parasites during their time in our facility. However, many home aquariums run at 1.024–1.026 salinity — a significant difference in salinity that requires a slightly slower acclimation to avoid osmotic shock.

If you run 1.024-1.026 salinity in your tank, make the following adjustments to your acclimation protocol:

• Extend the mixing period in Step 4 to 45–60 minutes total.
• Add smaller amounts of tank water (around ¼ cup) every 3–5 minutes instead of ½ cup.
• For sensitive fish such as tangs, wrasses, or butterflyfish, aim for the full 60 minutes if possible.

Always use an ammonia neutralizer during this time and do not exceed 60 minutes total acclimation time.

Optional: If you have a refractometer or salinity tester, you can check the salinity in the bucket before transferring the fish to ensure it closely matches your display tank.

Step 4: Gradually Mix in Tank Water

Add tank water to the acclimation container every 3–5 minutes, as described above. The total acclimation time should be 30 to 60 minutes depending on the salinity difference.

Step 5: Transfer Your Livestock to the Tank

Use a net to gently transfer your livestock into your tank or quarantine system. Never pour the shipping water into your aquarium.

Step 6: Lights Stay Off

Keep your tank lights off for 4 to 6 hours to help your new arrival settle in.

Quarantine (Optional but Recommended)

Although not required, quarantining new arrivals allows you to:

• Observe for signs of disease or parasites
• Avoid introducing pathogens to your display tank
• Help the animal recover and gain strength before joining tankmates (especially if you have more aggressive established species).

Common Mistakes to Avoid

• Floating the bag too long before opening
• Using a slow drip acclimation over 1 hour (can increase ammonia toxicity)
• Skipping the ammonia neutralizer step
• Pouring shipping water into your tank
• Leaving lights on during acclimation

Heavy Breathing, Lying on Side

• If you see heavy breathing, or if the fish is lying on its side, this is a fairly normal symptom of shipping stress (especially for Tangs, Wrasses, Triggers, Angels, and Butterflies), and your fish should bounce back within 24 hours.
  • Add an air stone or increase surface agitation, and make sure your return pump or wavemaker is running, to increase oxygen levels.
    
  • Check tank parameters
    • Ensure there is no detectable ammonia.
    • pH should be ~8.1-8.4
      
• Do not feed immediately — wait until your livestock is swimming normally and showing interest in food
• Ensure a peaceful environment for the new arrivals, separate from aggressive eaters and potentially territorial established tankmates.

Recommended Supplies

• Seachem Prime or other ammonia detoxifier
• Acclimation tools (turkey baster, measuring cup)
• Clean container or small bucket used ONLY for aquarium purposes

Note on Acclimation Boxes:

• Please do not place new arrivals in acclimation boxes. Your guarantee will be void for items that are placed in acclimation boxes upon arrival. 

• Acclimation boxes are stressful places to be, as the fish will be able to see different directions in which to swim, but unable to swim there. They are instead suspended in the tank, visibly exposed on all sides, which may make it difficult or impossible for them to de-stress from shipping.
  

• Extended periods of stress can potentially kill a fish or bring out underlying illness.

• If you are utilizing the acclimation box to avoid aggression from established fish, we recommend placing your established fish in the acclimation box, as they are not recovering from shipping stress. This will allow your new arrivals to settle into their new home in peace.