Two Yellow-bellied slider turtles are being cared for at Blue Reef Aquarium in Hastings after they were left there in a cardboard box.
A man walked into the aquarium on Sunday, and handed staff a box, asking them to look after what was inside it. He then left.
On opening the box, staff discovered the two turtles which were reported to be filthy and without water and in a very poor state.
The turtles have been named Bert and Ernie and they are currently in quarantine at the aquarium, where they are being kept under observation.
Blue Reef's Chrissie Daniels said: "Despite their ordeal they appear to be making a good recovery but we will keep monitoring them closely for the next couple of weeks to ensure they’re going to be okay.
"There is a growing problem with regard to people abandoning exotic pets like turtles. Unfortunately the owners buy these cute little creatures and either don’t realise, or fail to take into account the fact they will keep getting bigger.
"Terrapins and turtles start out about the size of a 50-pence coin but within a few years they can reach the size of a dinner plate or more and that’s when people start abandoning them," she added.
A special display tank is being built to accommodate the new arrivals, but staff warn that the aquarium is unable to cope with any more abandoned pets.
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