My brother has an amazing Salt water Aquarium. He like to experiment with different stuff and always pays extra attention to his aquarium.
As mention in the title this is a Hammer Head Coral which he planted recently in his aquarium.
It can expand upto 10 inches. But the most interesting part of it is that when it comes in contact with blue light, the colour changes and it's very pleasent to watch.
You can watch them for hours and still you will ot get bored of it.