Mike de Maine, the Aquarium’s technical manager shared this exciting news with Aquarium staff on Friday 1 April 2016. He followed this mail with another one reassuring us that it was not an April Fool’s joke!
It's two years since we broke ground for the new predator exhibit and much water has passed under the bridge since then. However, as Mike said, the tank is now in our hands and we can start preparing it as a home for animals.
As we have reported in previous blogs, building an aquarium this large is no mean feat and there are many elements to consider in order to ensure that it is a safe and habitable space for marine animals.
Several teams are now working simultaneously on the exhibit. Wild Exposure is the company doing the rockwork for us. The rockwork needs to be cleverly designed to hide aspects of the life-support system, to provide habitat for animals and to look aesthetically pleasing for our visitors. A model was built by aquarist Pierre de Villiers and Dr Pat Garratt, our now-retired CEO, so that they could figure out the best position and structure for the rockwork.
After climbing down the scaffolding into the exhibit and chatting to Ruan Schonefeld, the Wild Exposure foreman, I discovered just how intricate the rockwork construction is. The first part of the job is to the build the structure onto which the cement will be applied.
“Normally we would use steel for this, but because of the salt water we are using plastic piping. This takes longer than steel because we obviously can’t drill into the walls of the tank. So the plastic piping has to be fixed with glue on to the walls,” Ruan explained.
Once the piping is in place, a plastic screen mesh is applied to cover the pipes so that the cement has something to attach to.
“We first apply a scratch coat which is just a thin layer of cement and then we use the Putzmeister machine to spray the cement on,” said Ruan.
This is the only piece of machinery used in this entire job! The rest is all done by hand, by a crew of just seven.
“We will spray the cement on slowly because of the steep surfaces. It will be about 40 to 50mm thick. If it is too thin, then we won't be able to get the detail – like deep cracks – to make it look like rock,” he explained. “We also hand-carve the cement to create different textures.”
Once the cement has dried it will be washed down and painted with a colour which the Aquarium team still needs to decide on. A water-based PVA paint is used, which is diluted with water so that it penetrates the cement. The entire job will take approximately a month to complete.
Wild Exposure is no stranger to working in aquariums. They completed the ship at uShaka Sea World and worked in some of the smaller exhibits. They have also worked around the country – at Sun City, at the new water park at the Wild Coast Sun, the Cradle of Humankind and at the new De Beers Museum in Kimberley. They have also worked further afield in Zimbabwe, Namibia, Egypt and the United Arab Emirates.
While rockwork construction is under way our technical team is busy working on the life-support systems, installing the vertical piping for the sub-gravel filtration so that it will be hidden by the rockwork. Front of house, i.e. the visitor area, is also being prepared with carpeting and painting, audio visual equipment is being installed and signage designed.
It is all systems go for the Aquarium team and we are pushing hard to deliver a brand new, spectacular experience by the middle of 2016.
See more updates on the construction of the new exhibit here.