labman

I neither have tried to swim in Jell-O, or heard of anyone else doing
it. I will only guess, since I am not going to try it. It would be very
hard going if you tried. The Jell-O would break up and not go back
together as you passed through it because it is not a liquid. It is a gel.
It is mainly water, so you should be able to float in it. As thick as it
is, i don't know if you could actually pull it into you lungs the way
you would water. If you couldn't turn over and expose you nose and
mouth to the air, you could smother. Drowning is a special form of
smothering where your lungs can't get oxygen because they are filled
with a liquid.

Jell-O is a trade mark for flavored, sweetened gelatin. It should be
written with a capital J.

Createamate

A person would not be buoyant in a jello pool. One would dive in and not be able to get out alone.

labman

Can you document that the specific gravity of Jell-O is less than the human body? To the extent that it could flow after you disturbed it, it should continue to buoy up lighter materials. If you dove in at an angle leaving undisturbed material above you, you might or might not be able to fight you way through it.