Has anyone tried feeding jumbo shrimp from a fish market? I've heard their pretty fatty but I just wanted to know.

I haven't heard of anyone using them in their diet though as an occasional treat I wouldn't suspect them as causing any issues. I personally wouldn't use them as any sort of staple item however.

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They worked great when I was trying to put a bit more weight on the Red Eared Slider dropped off where I work, but I agree with rich, they probaly should'nt be offered as the primary diet.
I'm not sure about shrimp, but freezing some types of fish increases levels of an enzyme in the fish that destroys vitamin B1, so if you do feed shrimp, stay away from frozen shrimp.
RES should be offered a variety of animal and plant matter, with younger turtles generaly prefering more animal matter, and older turtles more vegtable matter.
I would suggest only about 25% of the diet being commercial turtle pellets,
The rest consisting of a variety of earthworms, bloodworms, crickets, aquatic snails, and occasionaly feeder fish, collard greens, mustard greens, dandelion greens, or kale. iceberg lettuce should be avoided.
They also seem to like carrots and squash.
You should also mix a good reptile multivitamin with calcium and vitamin D3 into the food a few times a week.

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