Do you really think in caves is more to be found, than on the seabed?

Most caves you will find, will look exactly like the cave before. Different types of rock. If you are lucky, crystals. In the deep sea, you have chances of finding entirely new species. (Only some caves have life at all)

Caves can have intricate ecosystems. There was an article on here some time ago how a single bag of chips completely altered the balance of a cave's fauna and flora.