A peep into the 200-foot-long mobile underwater fish aquarium in Visakhapatnam

A 250-foot-long mobile underwater tunnel aquarium visits Visakhapatnam. We weave through between sharks to find out how the organisers more they transport 2000 fish across the country

Arowana, sharks, gowrami and sting rays glide around us at this walk-through tunnel aquarium. A visit to the Underwater Tunnel Aquarium Exhibition at the ground behind AU Convention Centre at Beach Road takes us on a journey from the shore to the depths of the ocean.

More than 2,000 fish of 500 varieties are exhibited in the 250-foot-long tunnel aquarium, built at an estimated cost of ₹4.5 crore. The exhibition, which arrived at Port City from Nellore earlier this month, offers a unique experience of watching marine as well as freshwater fish up-close. Apart from the walk-through underwater tunnel, the exhibition also has 44 aquariums set up at the entrance.

Behind the massive exhibit are the efforts proprietor Raja Reddy and his team of experienced staff from Kerala. “Right from selecting the species to transporting them and setting up a system to maintain the right ecosystem, it is a long process. To support the aquarium unit in Visakhapatnam, we have a team of 18 that works round the clock in two batches,” says Raja, who has been in the business of amusement parks for over three decades.

Raja first came across underwater tunnel aquariums during his travels in Singapore, Malaysia and Dubai and was floored by the experiences. “I wanted to recreate a similar setup here but a movable one that can be taken across cities. The logistics and setup took a lot of time to fall in place. It had to be done in an immaculate way with the help of experienced staff who knew how to handle various fish species,” he says.

The most expensive fish at the underwater tunnel aquarium are the arowana, which cost ₹6 lakh each and are 3.5 feet long with an elongated body covered by a mosaic of large, heavy scales. The exhibition also has four leopard eels which costs ₹2.5 lakh each. These are marine fish found in tropical reefs in the Indo-Pacific ocean. They can grow up to 10 feet long and are characterised by their aggressive behaviour toward other fish. Adjacent to the eels are a pair of stingrays which are seven months old.

The underwater tunnel is made of glass that is of 52 mm thickness, which can withstand water pressure without distorting the view. About 1,200 litres of water is used for the tunnel while 600 litres is used for the aquarium tanks. The tunnel can be broken down into eight pieces and is transported in lorry containers without the fish. The fish are separately transported in 70 tanks, each 3.5 feet tall and eight feet long. “The tanks are transported through a truck which is attached to a 7.5 kilowatt generator that supports the oxygen generator,” says Raja.

At the tunnel exhibition, the support staff change the water every day. The filtration process begins at 11pm every night and goes on for 12 hours. A team of nine people is on guard day and night to monitor the aquarium, maintain conditions that imitate the salinity found in the natural environment of the fish and also keep suitable temperatures in the aquarium. “We maintain a maximum temperature of 28 degree Celsius. If the temperature drops below 20 degree Celsius, the fish can die. Higher temperatures are detrimental too,” he adds.