A new water world takes shape
From drop to habitat:
It can take a drop of water four months to make the journey from open water to an aquarium habitat alive with sharks, rays, corals, jellies and vivid tropical fish. The work of preparing that water is done by aquarium teams dedicated to the care of the creatures they support and the environments they represent.
At the Seattle Aquarium, these diverse environments are replicated in detail, including air, plants, lighting and features such as rocks and coral. The new
Ocean Pavilion will open in 2024, featuring sea life from the Coral Triangle, a marine area in the Western Pacific and Indian Ocean regions, and highlighting the ways ocean habitats are connected around the globe. The aquarium will use innovative, efficient technology to cleanse and recirculate water within a closed energy loop that heats and cools.
Most of the animals in the Seattle Aquarium’s care today live in the Salish Sea. As a result, water goes through minimal filtering and disinfection before being piped into the system and back into Elliott Bay. Water for freshwater fish habitats comes from the same city supply we drink daily, after first passing through a carbon filter to remove chlorine.
However, the new Ocean Pavilion will require a different approach, already underway. The multistep process will involve processes to prepare the water, including introducing beneficial bacteria, to ensure the well-being of the sea life.
It can take a drop of water four months to make the journey from open water to an aquarium habitat teeming with sharks, rays, corals, jellies and vivid tropical fish.
Aquarium water starts in Elliott Bay––an estuary with salty seawater and freshwater from rain streams and rivers.
11-meter pipe
The water's salinity will rise naturally by several points, with evaporation.
Water is run through a sand filtration system to pull out any solid larger than half a grain of rice.
Ultraviolet sterilization deactivates any of the pathogens and viruses natural seawater sometimes contains.
Heat exchanger
Sand filtration system
Adapting the temperatures to the tropical animals' preferred setting in the high 70s degrees Fahrenheit.
The building's air and water temperatures are managed by one controlled system, relying on green and regenerative energy use.
While ozone is harmful in excess — the aquarium is conservative in disinfection use.
Fractionation puts the seawater in a blender-like gadget to remove leftover particulates that can't be seen with the naked eye.
Then, the water is piped into the habitats. For the most part, it stays there, too — 96% of the water is recirculated and doesn't leave the building. Since the animals living in Ocean Pavilion are not from the Salish Sea, releasing water from their habitats back into Elliott Bay could have a negative impact on local species and ecosystems.
SECRET SAUCE: Bacteria
"Bacteria are the secret ingredient for an aquarium," Mewhirter says. Bacteria often have negative connotations because some types can make us sick. But beneficial bacteria do good work, Mewhirter says. "They're stalwart unpaid volunteers."
These beneficial bacteria convert nitrogenous wastes into less harmful versions of that waste. "Animals can live happy, healthy lives and thrive because bacteria exist robustly," Mewhirter says.
Premade bottled bacterial mixes can be added to an aquarium habitat as a shortcut. But mixes also present the risk of unintentionally adding an unknown element. So the Seattle Aquarium is introducing bacteria to the Ocean Pavilion using a different approach.
"Bacteria are the secret ingredient for an aquarium," Mewhirter says.
+
(ammonia)
(nitrate)
Animal wastes
beneficial bacteria are flourishing
After 4-6 weeks
Finally, habitats are fine-tuned for temperature, light and other factors, based on the animals' natural habitat. Open-ocean animals like guitarfish, rays and sharks like temperatures around 74-76 degree Fahrenheit, while corals crave 79-80 degree Fahrenheit temperatures.
Some aquarium life, such as corals or mangrove trees, needs additional light for photosynthesis in our Northwest climate. Specialized lighting provides extra intensity and wavelengths. Coral and even other animals need supplementation through nutrients, just like humans.
"Aquariums are full of really clever problem-solvers," Mewhirter says.
As a result, aquariums support the healthy, happy lives of animals the average person can't just pop out and see — many of us can't or don't know how to dive.
"We can still observe and connect with the ocean’s verdant underwater ecosystem and see what's happening beneath the surface. We're bringing the depths up to an accessible surface."
processed water
Then it's time to start introducing animals, slowly and intentionally, carefully testing the water daily. Larger animals eat more and produce more waste and can shift the water's balance — so it's a delicate, methodical process.
THE FINAL TOUCHES
The Seattle Aquarium is a conservation organization working to regenerate the health of Earth's one ocean. Support the Aquarium's mission of Inspiring Conservation of Our Marine Environment by going to seattleaquarium.org and following our social channels.
Ozonation & fractionation
From drop to habitat
MEET THE STAFF
Hannah originally hails from California’s Central Valley, known for its verdant agricultural landscapes and unrelenting drought. This lack of water fostered a fascination that led her to San Francisco, where she studied chemical oceanography and boundary layer dynamics. She nurtured her chemistry craft at the Monterey Bay Aquarium for seven years before trading Monterey’s moody marine layer for the Pacific Northwest’s perpetual mist. Hannah joined the Seattle Aquarium as the water quality manager in 2022 and delights in her ability to wax poetic about the intricacies of the seawater matrix, champion for data-driven decisions, solve perplexing “chemysteries,” and elicit coworker eye rolls with ocean-themed witticisms (are you having fin yet?! Sea what she did there?).
Hannah Mewhirter
Seattle Aquarium’s Water Quality Manager
"It's part of our commitment to stewardship," Seattle Aquarium’s water quality manager Hannah Mewhirter explains. "We want to do right by these animals by replicating the natural process."
The water quality team (from left): Juliette Horn, Keenan Wong, Tobias Brown, Angela Smith and Hannah Mewhirter.
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Water quality specialist Keenan Wong peers into an assay of ammonia tests.
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Sample bottles filled with habitat water for routine water chemistry testing in the laboratory.
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Learn more about Ocean Pavilion
By Seattle Aquarium