A power struggle has begun between two of the biggest aquarium residents in the UK as a new fish enters the fray.

Eastern Daily Press: Noah the green sea turtle at Great Yarmouth Sea Life Centre. Picture: Zac MacaulayNoah the green sea turtle at Great Yarmouth Sea Life Centre. Picture: Zac Macaulay (Image: © Zac Macaulay MMXII)

Noah, a Green Turtle, currently rules the roost in the Ocean Tank at Great Yarmouth Sea Life Centre, but is now facing competition from a Queensland Grouper, called Lance.

With his 90 kilogram bulk, sharp beak and armour-like shell, Noah can bulldoze rivals out of the way to get to the daily fish rations first.

But Noah has lost weight recently, whereas Lance, who weighed only two kilos and was just a foot-long when he arrived seven-years ago, is now five-feet long and weighs 44kg.

Staff has noticed that Noah is now beaten to the morning meal.

Eastern Daily Press: Noah the turtle is checked over by the Sea Life Centre divers after he was briefly taken out of the tank to be weighed. Picture: DENISE BRADLEYNoah the turtle is checked over by the Sea Life Centre divers after he was briefly taken out of the tank to be weighed. Picture: DENISE BRADLEY (Image: Archant)

Supervisor Stacy Adams said: “Lance has an impeccable built-in clock and always seems to anticipate feeding time and be in prime position when we arrive with our buckets of fish.

“He looks straight at us with those big doe eyes of his and it’s hard to resist casting the first morsels into his path.”

Ms Adams believes Lance has now reached maturity at nine-years-old. But he may not have stopped growing as Queensland Groupers can be more than eight-feet long and weigh 400kg.

She added: “Remarkably he had been living in someone’s home aquarium tank until he came to us five years ago.

“Thankfully his original owners soon realised he was going to quickly outgrow their tank, and probably eat every other fish in it too, and they brought him to us.

“They have visited once or twice a year since to see how Lance is getting on, and each time have been amazed at how much bigger he has grown.”

Lance’s annual health check required two divers to guide him into a net. Four people to then carry him to a temporary holding tank

“That enabled us to weigh him using a huge fisherman’s balance, and to carry out a thorough check of his whole body to make sure he had no infections or lesions,” added Ms Adams.

“Happily he proved to be in tip-top condition.”

After a few days of observation Lance was returned to the ocean tank and splashed about in obvious delight at being back in familiar surrounds.