Tube Sponge
Tube sponge is a non-solid sponge block.
Tube sponge can only be obtained using Shears or Silk Touch enchanted tools. If mined without, nothing is dropped.
Tube sponge generates in frozen oceans, in patches on the seafloor.
Tube sponge can be placed underwater, atop any solid block.
Tube sponge has 3 stages of growth, each visually distinct. It grows extremely slowly, but the growth speed can be increased by planting it atop a wet sponge block.