When you bonemeal a block underwater, mainly dirt or sand, the bone meal will create a piece of coral or seagrass, or others. However, once you use bonemeal on the side of the block and there is a coral or seagrass above the block then the bonemeal will get used like crazy!

To reproduce:

1. Go underwater
2. Grab some bonemeal
3. Go to a sand or dirt block
4. Bonemeal the SIDE of the block
5. A coral or seagrass will generate.

What happens is that right as the coral/seagrass generates, and you hold down right click on the side of the block, the bonemeal will then get used ULTRA FAST! What should happen is that the bone meal should be used slowly or not at all after the coral/seagrass is placed.