"Occurred on June 10, 2017 / Debary, Florida, USA
"My husband was bailing water out of our boat after a huge storm. Every time he threw the water we saw splashes in the water. I happened to be recording on one of the tosses and we saw huge splashes of water everywhere. We both looked at each other and said 'I will never swim in there again!'"
I've been up and down the comments, and can't find a definitive answer as to what it is... The guesses are alligators, (invasive) carp and manatees... Does anyone know for a fact what it is? Because I'm not going near any body of water until I do...