These light bulbs appear to be actually full of water. The bubbles in the water were likely part of the water photo, or even the fish, but look like they are inside the bulb. The highlights and shadows on the bulb make it appear rounded and realistic.
More than a ship in a bottle, an entire storm and sufferer. They look like something that would be fantastic to have as a home decoration, if such things existed. Such a cool idea and I love how they were able to capture that true storm effect in the jar