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Recently, I had the chance to observe as Stacey Tidman in the Animal Care Facility vacuumed, sorted and scrubbed the Pacific tank.
A suction tube removes waste from the gravel in the Pacific tank.
The process starts with emptying some of the dirty water from the tank. The Pacific Habitat is a saltwater tank, so white crusts of salt build up everywhere. These have to be wiped away. Then Stacey fires up a large suction apparatus that pulls the detritus (waste and uneaten food) from the gravel bed at the bottom of the tank. This sucking tube is equipped with a screen so that no valuable sea creatures (like the worms that live in the gravel bed) end up going down the drain.
The next step is to remove any empty mussel shells. The starfish and sea urchins that live in the Pacific habitat love to snack on mussels, and the Museum staff provide them with a steady supply. The staff leave a few mussel shells in the tank as a source of calcium.
Finally, Stacey scrubs the algae growth off the inside of the tank. There are snails in the habitat that help keep the tank clean by eating algae, but sometimes they need a bit of assistance. Stacey uses a special fibrous mitt to remove the algae from the tank without damaging the Plexiglass.
Scrubbing a week’s worth of algae from the Pacific tank.
But bath time isn’t just a chore; it’s also a chance to get hands-on experience with some really beautiful and fascinating creatures. In my next post, I’ll introduce you to the colourful residents of the Pacific tank.
The Fresh Water aquarium isn’t the only aquarium in the water exhibit! The Pacific aquarium holds 120 gallons of water and will be the first thing visitors see when they walk in. Since this aquarium will be situated right at the front, exhibit designers decided that the visitor’s first impression of the gallery would ideally be Zen-like, and really shouldn’t include the loud buzzing and noises made by the aquariums mechanical support. To avoid this, parts of the mechanical set up will actually be installed above the washrooms just outside the exhibit! The aquarium and its mechanical support system have just been unpacked and therefore it isn’t installed yet, but once it is up and running it will have specimens like anemones, star fish and urchins amongst many others and will act as a wall between the doors and the blue whale. Once visitors walk around the pacific tank they will see the blue whale for the first time, and hopefully experience the “Wow” factor that comes along with displaying a specimen that is 65 feet long. Stay tuned for progress on the Pacific aquarium!
The Pacific Aquarium in the Gallery Entrance
There are fish in the Fresh Water aquarium! A few Emerald Shiners have been introduced to the aquarium as part of the process of establishing the biological system, and the fish are doing their jobs well! Immediately after the fish were introduced, ammonia levels in the aquarium spiked a bit which was expected, since fish naturally excrete ammonia. However, since then ammonia levels have been dropping which means there is some successful biological activity in the tank that is naturally starting to deal with the ammonia. No supplements have been added in close to a week which also confirms that the fish are doing their jobs! Staff will continue to introduce Shiners to the tank until the biological system has been fully established and it is safe to introduce the permanent specimens to the aquarium, which will include clams, mollusks and bass.
Emerald Shiners in Fresh Water Aquarium
I assumed the process of changing the water in this giant aquarium would be complicated; however after witnessing a water change today I realize it is actually very efficient and well thought out. Everything is done from the mechanical room and involves turning a few knobs to open and close some shut off valves. Of course the process is closely monitored to make sure the proper amount of water comes in and out as well as making sure the water is the correct temperature, but the manual labour involved in changing the water is minimal. The new water that is brought into the tank is just tap water from the city which is very cold and could therefore change the temperature of the aquarium by 2 or 3 degrees, which is stressful on the fish, but also helps level out ammonia. Monitoring the temperature is important, but again is largely managed by the machines that support the aquarium. Overall, the process of changing the aquarium water is beneficial not only to museum staff but also to visitors because once the exhibit opens it means their visits won’t be interrupted by maintenance work. Visitors won’t even be able to tell when the water is being changed even when it’s happening right before their eyes!
Last week we met the spotted turtles that will soon be calling the water exhibit home. Now it’s time to meet the freshwater fish and the Pacific habitat fish…
The residents of the freshwater river habitat have presented a bit of a challenge for the Museum staff. This habitat will include a variety of fish species collected from the Ottawa and Rideau Rivers. Determining which species could coexist peacefully in the habitat has been a learning process. For example, the staff tried to keep a group of large- and smallmouth bass in a tank with a group of Bluegill fish. But the bass decided that the Bluegills would make better snacks than roommates – they ate half of the Bluegill population in one night. For now, the more aggressive species of freshwater fish are kept in separate tanks in the Animal Care Facility. When the fish go on display, these predatory species will be separated from the less aggressive fish by an invisible Plexiglass barrier that bisects the freshwater aquarium.
Some large- and smallmouth bass daydream about tasty Bluegill fish.
There may be conflict between the freshwater river fish, but the residents of the Pacific habitat are getting along just fine. The Pacific tank, which is already on display in the Museum’s cafeteria, is a biodiversity habitat, meaning that it contains many different species that can live in harmony. The water in their tank is kept at a cool 9 degrees Celsius. This relatively low temperature means that they don’t eat too much (and therefore don’t produce much waste), so a large number of animals can share the habitat. This tank includes a wide range of vertebrates (including a foot-long gunnel fish) and invertebrates (such as brightly-coloured starfish). Each day, these laid-back West Coast species receive their nutrition in the form of an “algae shake.” It’s not very appetizing-looking, but it seems to hit the spot.
Having a lengthy acclimation period is extremely important for both the animals that will be living in the exhibit and the staff who will be caring for them. It means that that there will be fewer surprises (and fewer conflicts between tank-mates) when the water exhibit goes live in May.
As Museum staff members are busy preparing the new aquarium, the exhibit’s new inhabitants are getting ready for their big debut.
The Museum’s water exhibit will feature three live habitats: a turtle habitat, a freshwater river habitat and a Pacific habitat. Many of the animals that will live in these habitats have already arrived at the Museum, but they must go through a lengthy acclimation process before they can go on display. They must get used to being around people, noise and, in some cases, each other.
For over a year now, two spotted turtles have been hanging out in the Animal Care Facility at the Museum, preparing to move into the turtle habitat. Spotted turtles are the smallest turtle species found in Canada, and while they are native to the Ottawa area, they are somewhat rare. These particular turtles came from the Ecomuseum in Montreal. The Museum of Nature staff have been monitoring the turtles, making sure they are healthy, happy and getting along. Their habitat in the water exhibit will simulate their habitat the wild, and will include a selection of other animals, such as mussels and crayfish.
A spotted turtle relaxes on a log in the Animal Care Facility.
Next week…we meet some feisty freshwater fish and some very cool creatures from the West Coast.
In order to establish a healthy biological environment which will naturally control ammonia levels, staff has used a biological supplement in the aquarium to speed the process up a bit. The supplement provides powerful, beneficial bacteria that will allow for the growth of flora which will metabolize high amounts of ammonia and nitrites (another harmful chemical for fish!) in the aquarium. Usually it takes 6-8 weeks for an aquarium to establish a biological system on its own, however staff is attempting to speed the process up so the aquarium will be thriving, lots of things will be growing and the fish will be used to their new home by the time the exhibit opens in May. After introducing the supplement to the aquarium, staff tested the levels the following day and discovered the ammonia levels had been reduced by half! They also found that nitrite levels were nearly zero which is excellent news for the fish. Staff will continue to test the water to maintain healthy levels and if all continues to go well more fish will be introduced to the tank soon!
Testing ammonia levels
An important step in setting up the fresh water aquarium, where plants and fish will thrive is making sure the water chemistry is healthy and can support the specimens living there. After initially filling the tank and introducing a few fish as part of the seeding process, staff found that the levels of ammonia in the water had spiked since fish release ammonia through their gills, waste and urine. In an aquarium that has an established biological system ammonia is naturally fought off without threat to the fish, but part of the challenge in developing a healthy aquarium environment is controlling these levels so all the new fish and plants coming in will be healthy!
If you were wondering about the “Do Not Clean” sign on the side of the aquarium, it isn’t because the museum is opposed to cleanliness, but to prevent a potential well meaning cleaner from coming along and using a product like Windex which contains ammonia, and could damage the aquarium!
Staff member extracts water for testing
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