Archive for Aquarium
This Job Never Gets Cold
After spending 113 hours and 36 minutes under water in 2013, the zoo’s Dive Team is far from “all wet!” The divers, along with support from staff on the dry side, completed 85 dives last year in their quest to keep the zoo’s Great Barrier Reef tanks sparkling clean.
Though the 78 degree water temperature sounds balmy, Aquarium Area Manager and Dive Safety Officer Gary Stoops says divers need to wear wet suits to retain body heat, which is lost faster in water than in air. The thick wet suits also protect divers from aggressive fish. “Some of the fish are very territorial. The triggerfish and even the zebra moray eel have been known to challenge the divers, and even nip at their wet suits.”
The shark tank is a different story. No diver has ever been bitten during a dive with the blacktip reef sharks. “They just stay away from us,” states Stoops.
When the zoo is open for the season, guests can witness dives and can even get involved in an interactive dive chat! Divers are outfitted with a speaker and microphone that allow for live question-and-answer sessions. Dive Chats are held every Wednesday and Thursday at 1:30 PM.
All-told, divers spend about 90 minutes in the water during each dive. Most of that time is spent cleaning the coral, and of course avoiding the eel. At 15, he is the aquarium’s oldest resident and is an expert at defending his territory.
Spring Cleaning at the Aquarium
After moving the hundreds of moon jellies to a back-up tank, 500 gallons of sea water are pumped out of the tank. When the water level is too low for the pump, aquarists Gary Stoops and Ian Wallace resort to the old fashioned method of bailing the water with a scoop and bucket.Once a year, the Great Barrier Reef Aquarium crew takes on a daunting task: draining, cleaning, and scrubbing the two 500-gallon jellyfish tanks.
“Once we have all the water out, we will scrub the tank walls to get rid of the old food, polyps, and debris that settle on the floor and walls of the tank,” Stoops explains.
The moon jellies eat brine shrimp, and some of the unhatched brine shrimp eggs fall to the tank floor. Polyps are the result of jellyfish reproduction, but these tiny jellies do not survive in the confines of the aquarium.
This spring cleaning event results in a major water change for the jellies, with about 80% of their tank water being removed and replaced (about 20% of the water is pumped into a sump, and will be added back to the tank). For many aquatic species, this would present too much of a shock, but Stoops says, “Moon jellies are pretty hardy.”
Stoops mixes up artificial sea water for the tank, which mimics the natural ocean in that it contains traces of nearly every element on earth. Once the water cycles through the filtration system, it will be ready again for the moon jellies.
Click on the photos below to enlarge.