Step 5: The Optional Dachshund step
Watch him go!
The glove is under massive pressure and stretched to it's limit. All the elastic energy is released when Zak bites it, the rubber retracts around the mass of water too fast to see.
The result is a perfect Aquaglove shaped blob of water in mid air, amazingly captured at just 15 fps.
See the intro step for a slowed down video of the burst, and below for individual freeze frames.
An alternative glove option - Purple Nitrile Laboratory glove