Cleaning windows can be a straightforward task – but when you're 20ft underwater, accompanied by sharks and tied down by scuba diving equipment, the job suddenly becomes a lot harder.

A 300kg sea turtle, blacktip reef shark and guitarfish were just three types of sea creatures joined by army divers as they spruced up the tank of a Norfolk sea life centre.

Ten soldiers from the 23 Parachute Engineer Regiment at Woodbridge, near Suffolk, squeezed into their wetsuits to clean the ocean tank at Great Yarmouth's Sea Life Centre on Monday.

Eastern Daily Press: One of the divers from the 23 Parachute Regiment cleans the large Ocean Tank at the Great Yarmouth Sealife Centre, watched by his colleagues. Picture: DENISE BRADLEYOne of the divers from the 23 Parachute Regiment cleans the large Ocean Tank at the Great Yarmouth Sealife Centre, watched by his colleagues. Picture: DENISE BRADLEY (Image: Copyright: Archant 2018)

Cpl Ryan Wood, 28, described the dive as a 'brilliant experience'.

He said: 'It was really good to be able to dive with all the sea creatures. It is not something we usually do, so it was a brilliant experience. The dive was a great way to practice our skills, particularly our buoyancy, as we weren't just walking along the bottom of the tanks.

Eastern Daily Press: One of the divers from the 23 Parachute Regiment waves to Sarah Bird and her son, Jude, aged two, as they clean the large Ocean Tank at the Great Yarmouth Sealife Centre. Picture: DENISE BRADLEYOne of the divers from the 23 Parachute Regiment waves to Sarah Bird and her son, Jude, aged two, as they clean the large Ocean Tank at the Great Yarmouth Sealife Centre. Picture: DENISE BRADLEY (Image: Copyright: Archant 2018)

'It is great to be able to help out a business in the local community and hopefully they are pleased with the job we have done.'

Divers used the Sea Life assignment to help with their underwater training. The army needs qualified scuba divers in its ranks for tasks such as removing underwater obstructions that may be impeding boats.

Eastern Daily Press: Noah, the green sea turtle, keeps an eye on the divers from the 23 Parachute Regiment as they clean the large Ocean Tank at the Great Yarmouth Sealife Centre. Picture: DENISE BRADLEYNoah, the green sea turtle, keeps an eye on the divers from the 23 Parachute Regiment as they clean the large Ocean Tank at the Great Yarmouth Sealife Centre. Picture: DENISE BRADLEY (Image: Copyright: Archant 2018)

Shane Breadmore, 24, is an aquarist at the centre who usually helps to clean the windows.

It is done once a week to remove the algae from the tanks.

Eastern Daily Press: Divers from the 23 Parachute Regiment, clean the large Ocean Tank at the Great Yarmouth Sealife Centre. Picture: DENISE BRADLEYDivers from the 23 Parachute Regiment, clean the large Ocean Tank at the Great Yarmouth Sealife Centre. Picture: DENISE BRADLEY (Image: Copyright: Archant 2018)

'I think they have done a really good job,' he said.

'It is not as easy as it may look, so I am really impressed with what they have done.

Eastern Daily Press: Divers from the 23 Parachute Regiment, clean the large Ocean Tank at the Great Yarmouth Sealife Centre. Picture: DENISE BRADLEYDivers from the 23 Parachute Regiment, clean the large Ocean Tank at the Great Yarmouth Sealife Centre. Picture: DENISE BRADLEY (Image: Copyright: Archant 2018)

'Diving with the sea creatures is a really surreal experience and I am sure it is one they will not forget for a while.'

The Sea Life Centre is home to a number of curious creatures, including penguins, crocodiles, jellyfish and sharks.

Eastern Daily Press: Noah, the green sea turtle, keeps an eye on the divers from the 23 Parachute Regiment as they clean the large Ocean Tank at the Great Yarmouth Sealife Centre. Picture: DENISE BRADLEYNoah, the green sea turtle, keeps an eye on the divers from the 23 Parachute Regiment as they clean the large Ocean Tank at the Great Yarmouth Sealife Centre. Picture: DENISE BRADLEY (Image: Copyright: Archant 2018)

But it is Noah the 300kg green sea turtle who captures the hearts and imagination of most visitors.

He even left his mark on one of the divers by taking a nibble at his ear.

Eastern Daily Press: Noah, the green sea turtle, keeps an eye on the divers from the 23 Parachute Regiment as they clean the large Ocean Tank at the Great Yarmouth Sealife Centre. Picture: DENISE BRADLEYNoah, the green sea turtle, keeps an eye on the divers from the 23 Parachute Regiment as they clean the large Ocean Tank at the Great Yarmouth Sealife Centre. Picture: DENISE BRADLEY (Image: Copyright: Archant 2018)

Cpl Wood said: 'Noah was definitely my favourite – he was always keeping an eye on us, and even took a closer inspection at one of our lads.

'He was a lot of fun.'

Eastern Daily Press: The divers from the 23 Parachute Regiment based at Ipswich, after cleaning the large Ocean Tank at the Great Yarmouth Sealife Centre. From left, Cpl Lee Ord, Lance Cpl Carl Pick, Sgt Paul Hodgkinson, Major Stuart Lee, and Cpl Ryan Wood. Picture: DENISE BRADLEYThe divers from the 23 Parachute Regiment based at Ipswich, after cleaning the large Ocean Tank at the Great Yarmouth Sealife Centre. From left, Cpl Lee Ord, Lance Cpl Carl Pick, Sgt Paul Hodgkinson, Major Stuart Lee, and Cpl Ryan Wood. Picture: DENISE BRADLEY (Image: Copyright: Archant 2018)