Snappers in northern VA will eat a plant called "Lizard's Tail" - it grows along the banks, and they'll actually come out of the water to pull the plants into the water so they can eat it. So, I'd try water hyacinth, anacharis, and other common aquatic plants eaten by sliders and such. Doesn't hurt to try the old staples like red leaf lettuce and water cress from the grocery store.
Katrina
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0.1 Iguana - Tiffel
1.2 Eastern Mud Turtles - Fred, Ethel, Edith
0.0.1 Giant Mex. Musk Turtle
Foster turtles: More than I'd like the husband to know about.