The yellow tube sponges featured above are about as close as I got to seeing “Sponge Bob” while scuba diving. Yellow Tube Sponge Link
As much as sponges look like plants, they are really animals. They are filter feeders that consume microscopic plankton. They come in many different shapes, sizes and colors.
Here is a link to some great information on sponges. I love photographing sponges… they don’t run away 🙂