In addition to what others have stated, I used to offer my very large adults......pre-killed pinkie mice! Earthworms were a staple, along with the occasional frozen fish and cooked shrimp pieces (plain shrimp - buy it raw, freeze, pop it in the microwave with a little water for 30 seconds, break into pieces), and an occasional defrosted pinkie once the T. natans were big enough to handle them.

Katrina
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1.2 Eastern Muds - Fred, Ethel, Edith
0.1 Iguana - Tiffel
0.1 Bearded Dragon - Foster
Foster turtles: More than I'd like the husband to know about.