"They are the number 1 animal we get turned into our rescue. We literally get them in almost every week," said Mike Hopcraft, owner and operator of The Reptile Guy
"People buy them when they're tiny little turtles. They don't realize how big they get."
Hopcraft said his rescue facility and education centre houses dozens of unwanted animals, from scorpions to bearded dragons.
Currently he has 81 sliders — more than his current tank can safely house — and today he plans to take 20 of them to a veterinarian to be put down.
Hopcraft said he wants to make sure there's room at the facility to continue to accept new turtles.
Otherwise, he said, people will drop off their unwanted animals in local ponds and lakes, where they wreak havoc on the ecosystem.
Hopcraft said his entire facility is overcrowded, and has launched a fundraiser on crowdsourcing website Indiegogo to fund a bigger rescue centre.
"We've had to start doubling up our snakes, doubling up our iguanas and tortoises, simply because there's nowhere to put them," he said.