Setting up an aquarium in a museum is not as straightforward as you might think, especially one that holds 1000 pounds of water! There are mechanical, chemical and biological factors to consider when installing a successful and thriving tank. This particular aquarium will eventually hold a variety of species including both predators and prey. How is it possible that both predators and prey can survive in the same aquarium for longer than a few minutes? Well the tank is actually divided down the middle by a sheet of clear Plexiglas, which is imperceptible even when standing right next to it. One side will feature smaller fish which would usually be food for the bigger fish that will live on the opposite side of the tank. This will allow museum visitors to see both kinds of fish together, but saves staff the trouble of having to constantly replace the smaller fish!
The division in the aquarium is noticeable in the photo above, because the left side has been cleaned recently, and the right side has not! The aquarium is looking much cleaner than last week, and this is because staff has been spending a few hours everyday cleaning the filters, scrubbing the sculpture inside the tank and moving the rocks around to get rid of all the dirt and grime that has accumulated. These are all things that need to be done to begin the process of creating an environment where fish can survive. Another important step is something called “seeding” which involves introducing a few small fish to the tank so they can start to contribute their fish-like qualities (like their feces!) to the environment. Fish feces contain digestive enzymes which help establish a successful biological system in the aquarium, or any environment they inhabit. Does this make you think twice about going for a swim in a big fresh water lake?
Of course, not everything found in the aquarium is useful. There is a large mechanical component to maintaining the aquarium, which is kept in a separate room in the back corner of the exhibit. This is necessary because once construction is completed the top and bottom of the aquarium will be enclosed and surrounded by information panels, limiting access to the aquarium. The white tube in the tank which is semi visible near the top (but will be completely disguised eventually) is a surface skimming tube that is hooked up to the plumbing and sends the debris it collects to the filtration system in the back room. After the initial installation of the aquarium, as well as filtering out chemicals, dust and dirt, staff members were even finding big chunks of plastic in the filters! It will be about 3-6 months before the tank and the mechanical systems will be running smoothly and relatively by themselves, requiring less work from staff, and minimal maintenance. Once the exhibit is done and the cleaning and filtration systems are functioning to their full abilities, the water in the tanks will only need to be changed at a rate of 10% a week. This is what is expected, but of course a certain amount of trial and error is involved, so it’s hard to say for certain how things will be run in the future. Hopefully according to plan!