Corals have been added to the "Coral Reef Sea" aquarium.

Did you all see the article about the "Coral Reef Sea" aquarium published in October 2025? (The mission of the fish in the "Coral Reef Sea" aquarium) Last time, we talked about the mission of the many fish in the aquarium. This time, we have added corals to the aquarium.

On November 28, 2025, corals were delivered to the "Coral Reef Sea" tank from Nishinoomote City, Kagoshima Prefecture. They come in a variety of sizes, colors, and shapes, from palm-sized to large enough to hold in your arms. All of the corals were housed as planned, separated into the "Coral Reef Sea" tank and the back yard. I was very excited to see some coral species I had never seen before.

However, this is where the real challenge begins. Simply creating water suitable for coral breeding can weaken the coral or cause it to become covered in algae. You must also adjust the water flow, light intensity, and brightness to determine which location in the aquarium is best for the coral to grow.

So, I decided to break off large corals into small pieces and place them in various locations with different conditions, such as water current and light, to find a suitable environment. I first placed the pieces glued to the rocks, and if they looked like they could live there, I moved the larger corals in. I'm still struggling to find a suitable location for the corals, so you can see that there are lots of small coral pieces in the tank.

By the way, some of you may be wondering whether it is okay to break coral. In fact, coral is made up of many small creatures called "polyps," similar to sea anemones, that gather together to form a single mass. Therefore, even if a part of the coral is cut off, it can still survive and continue to grow.

There are more corals than in our last introduction in October, and the Coral Reef Sea aquarium has come one step closer to recreating the rich environment of a coral reef. We encourage you to take your time to observe the corals in a variety of colors and shapes that you have never seen before.

[Kana Hirota, Animal Care and Exhibit Officer at Tokyo Sea Life Park]

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