I know it wouldn't work because that would make it a perpetual motion machine.
And if some simple troll science guy came up with a working perpetual motion machine.
Then god damn what the forget has Stephen Hawking been doing.
It wouldnt work because if helieum was put inside of the baloons they would ALL float upwards.
IT DOESN'T HAVE TO BE HELIUM, STUPID.
Just the average mixture of oxygen, nitrogen, and everything else found in common air would float in water.