Welcome to the Giant Ocean Tank!
This four-story habitat features a coral reef and hundreds of Caribbean reef animals, including sea turtles, stingrays, eels, and fishes. At its deepest point, the Giant Ocean Tank goes down 23 feet. It is 40 feet wide and holds 200,000 gallons of salt water. This exhibit is so big that, 50 years ago, it was built first, and then the rest of the Aquarium was built around it!
Use of Nest products is not an endorsement by the New England Aquarium.
Daily Dive Times:
10:00 a.m. – Feeding Dive
2:00 p.m. – Maintenance Dive
3:00 p.m. – Feeding Dive
Frequently Asked Questions
What is the temperature of the water and where does the water come from?
The water in the Giant Ocean Tank (GOT) is pumped in from Boston Harbor. After being filtered, it is warmed to a temperature of 74º F (24ºC).
How many gallons of water are in the GOT?
The GOT holds about 200,000 gallons of water. This water is re-circulated through filters about every 90 minutes.
What are the dimensions of the GOT?
It is 40 feet in diameter and 23 feet deep.
Is the reef living?
No, the reef is not living. The coral in the Giant Ocean Tank is made out of fiberglass and resin. The reef is very detailed and the corals you see are molded from actual coral skeletons to reflect what species of coral would be living on a Caribbean reef. Our exhibit designers also placed the artificial corals in places that mimic where you’d find them in the wild.
How many fish are there?
There are approximately 1,000 individuals in the GOT, from about 100 different species.
Where did you get the fish?
Fish come to us in a few different ways! We raise a lot of our most numerous species through our larval fish rearing program and partner to raise fish with many different institutions.
We also conduct expeditions to the Bahamas about once a year with a wish list of species we’d like to add to the exhibit. We receive special permission from the Bahamian government to conduct these expeditions and we also conduct surveys of the reefs to assess their health.
We also do some local collecting for our Caribbean exhibits in New England! Every year the Gulf Stream brings tropical fish to the New England coast and they can survive while it is warm enough in the summers. Our divers look out for these tropical species and rescue them before temperatures get to cold so that they can live out their lives at the aquarium!
Do the fish ever reproduce?
They do! Some of the eggs produced on exhibit may be removed by the filtration system unfortunately, but our divers can collect eggs laid on exhibit and raise them behind the scenes.
Some of the fish we’ve been raising are lookdowns, smallmouth grunts, neon gobies, and blue and brown chromis.
What happens to the fish waste?
The filtration system is home to many different components that can remove debris and harmful waste products form the water. The filtration (or Life Support System) uses pumps, filters, and even bacteria to help clean up the fish waste! Our Giant Ocean Tank aquarists also help this process by vacuuming and scrubbing the exhibit daily!
What are the largest and smallest animals in the exhibit?
There are many smaller fishes in the GOT, such as gobies and chromis.
The largest animal is a lot easier to find: our Green Sea Turtle, Myrtle. She wins the prize for largest animal in the Aquarium! She’s about 550 pounds!
Why don’t the sharks eat the other fish?
Our sharks and many of the other larger predators are target trained by our Giant Ocean Tanks aquarists. This means that they participate in a particular feeding method to make sure they are getting all of the nutrients they need. The diets and feedings are tailored to different species based on what they would eat in nature and how many calories they need to stay healthy. By getting their nutrients from our staff, they aren’t motivated to go after their exhibit-mates like they would have to in the wild to survive.
How do you know which fish you have fed and which haven’t eaten?
Our Giant Ocean Tank team have the awesome responsibility of feeding all of the animals in the GOT and keeping the exhibit clean. Every day, the divers feed the animals from inside the exhibit several times and offer multiple surface feedings. Each feeding dive, there are different species targeted to feed. After the dives and surface feedings, our team takes meticulous notes and enters their observations in a database to keep track of all the animals’ diets and health records.
Do the fish sleep? Do you turn the lights off at night?
The lights in the GOT recreate many of the natural variations that light has in nature. The Giant Ocean Tank goes through a twilight, sunrise, and sunset as well as having cloud cover change the intensity of light during the day. Overnight, most of the lights are off, but we also recreate moonlight with a single lighting fixture. This is important for nocturnal species that would depend on some moonlight for the active part of their day!
Sleep in fish can be complicated and varies from species to species. For some, sleep is just a resting phase but most of their movement including swimming stays the same. Other species do settle down at night and sleep in different spots around the reef!
Where did you get the turtles?
Our two loggerhead sea turtles are rescued turtles which means they came to the Aquarium for rehabilitation. They stranded on Cape Cod decades ago during a “cold-stunning” event. They stay with us for various reasons that require special care, including poor eyesight and neurological damage.
Myrtle, our Green Sea Turtle, came to us 50 years ago from another aquarium that was closing its doors!
What do the turtles eat?
Myrtle eats lettuce, Brussels sprouts, broccoli, cabbage, and other vegetables throughout the day. She also gets some protein usually in the form of squid, clams, and other seafood.
The loggerhead turtles only eat squid and fish because their natural diets don’t include the vegetation that green sea turtles do!