I shot several videos this trip using a GoPro Hero 4 attached to the underwater housing for my camera. I was very impressed with the quality of the video that the GoPro takes. It does look a lot better in 1080p as I shot it instead of the lower resolution that shows up on youtube but I don't have any way of posting such a large file here.
I hope you enjoy this swim with a turtle. It's a little long, about 5 minutes, so pour yourself a beverage of your choice and enjoy.