An underwater party took place in the world's largest Great Barrier Reef exhibit - and all the fish were invited.
Sea Life Sydney aquarium in Australia turns 25 this year and as part of its ongoing birthday celebrations aquarists donned fancy dress costumes to swim underwater with Black tip, Leopard and Grey reef sharks, along with the other occupants of the two million litre exhibit.
The party also featured a giant inflatable cake.
Over the past 25 years more than 140,000 animals have called Sea Life Sydney home. An incredible 29,000 gigalitres of water has passed through its exhibits and there have been almost 1000 births.
Two of the Grey nurse sharks and two lungfish have been resident since the aquarium first opened its doors in 1988.
Over the past 25 years more than $700,000/£425,300 has been raised for marine life conservation as part of the aquarium's Breed, Rescue, Protect programme.
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