Acclimating Fish to a Reef Tank

Acclimating Fish to a Reef Tank

Minimizing stress is the name of the game when acclimating fish to a reef tank so it is important to follow some some basic rules to ensure fish have a healthy transition to their new environment. Step one is to equalize the temperature of the water in the bag with the temperature of the tank. This can be done by floating the sealed bag in either the sump or tank for approximately 15 to 20 minutes.

acclimating fish to aquarium

Once the temperature is equalized, the fish can be removed from the bag by cutting open the top and pouring the water into a temporary container such as a five gallon bucket. Just make sure there is enough water in the container for the fish to be upright so it is not flapping around on its side. Don’t add tank water if there is not enough water in the container. Adding a lot at once can stress out fish so keep a smaller back-up container by your side in case this happens.

Small amounts of water from the tank can now be added gradually to the container. I like to add a cup of water every five minutes for about a half an hour. Of course the amount of water you add might vary depending on the amount of water in the bag. A big fish needs to be transported with more water so it might be necessary to add more cups of water over a longer period.

The fish is ready to go into the aquarium once a sufficient amount of tank water is added.  Many use nets but I typically avoid them since fins and gills can get stuck in the netting. My preference is to use a small cup or rectangular container. I simply guide the fish into the smaller container and then tip it to drain as much water as possible, cupping the top to keep the fish from passing through (fish stores use some non-reef safe medications to treat fish for disease so play it safe and don\’t add their water to your tank).

You don’t want the fish to have contact with your skin during this “cupping” process, it can damage its slime coat, so wear protective gloves or keep those digits at a safe distance. Once the water is out of the cup you can place it in the tank and let the fish swim away. Sudden exposure to light is another source of stress during the acclimation process so ideally it is best to keep things on the dark side during the entire procedure. It is also wise to keep the lights off in the tank when adding new fish since it will be tougher for other fish in the tank to give the the new guys in town the “business”.

The drip method is another way to go when acclimating fish and is something I would recommend for very sensitive fish. After floating the bag to equalize the temperature, the fish is placed into a container and a drip line is started via a siphon, drip by drip, from the tank to the container. This is a more gradual acclimation process than the one I went into detail on above.

To help you visualize my acclimation process, please check out this video of some Anthias I added to my new reef tank. I am going to apologize in advance……I did the acclimation with light….a no no for sure! Hey, I wanted to shoot a video to document the process so I kept my fingers crossed that it would do no harm. As it turned out, the fish were just fine.

Additional Resources

If you would like some help with a new tank build, including help designing a custom aquarium, or help re-configuring your current setup then you can visit this page for more information. And if you are looking to add some equipment, I do sell GHL, Pax Bellum, Reef Octopus Calcium and Kalk Reactors and Royal Exclusiv products, including Dreamboxes, which is the equipment I use and recommend. I also sell Reef Brite metal halide and LED fixtures as well as Maxspect & IceCap Gyres.

As for additional insights and information, please explore my many other reef tank and SPS related articles as well as my YouTube channel. For an even deeper dive into reef tank care you can check out my Reef Keeping Master Class. This online course is an immersive and one of a kind educational tool designed to help reef aquarium hobbyists build and maintain a beautiful SPS reef tank. The course is a series of video presentations with some supplemental video from my YouTube channel. There are also quizzes to help students retain and understand the information presented in the course.

Need some frags…..I can help with that as well 🙂 Please visit my SPS Frag store to see what is available.

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