"Monster" brindle bass, pilchard bait balls and a huge ticklish turtle called Bob - there's a lot more to Cape Town's underwater world these days than kreef and shipwrecks.A vast new exhibition tank at the city's Two Oceans Aquarium will feature some colourful new characters, including yellow-fin tuna and a guitar shark.The newcomers will join fish from the aquarium's main attraction, the predator tank, which is being turned into a "sharks only" exhibit. It currently accommodates both predator and prey, ogling each other while circling a giant hollow rock.The renovation project involves the tricky process of removing sea life from the predator tank, including ragged-tooth sharks.The first two sharks were removed yesterday using the novel "plastic sleeve" method.A team of divers herded the sharks with wooden sticks into the waiting sleeves, which were then hoisted to the surface and transferred into holding tanks.Meanwhile, a second 1.7million litre "ocean exhibit" is shaping up to accommodate less predatory creatures, among them a friendly turtle called Bob.Aquarium curator Maryke Musson said Bob had been found in bad shape but he thrived in captivity and had a "ticklish" shell.He will be joined in the new tank by several other crowd-pleasers, including the guitar shark...