The Glowstone Ocean is a dimension,added in X.0.To create the portal,put a shallow hole in the grass.Then,surround it with glass panes.Then,surround the glass panes with stone.Then,surround the stone with glowstone.Then,put water in the hole.Then,throw a glowstone shard in the water.Then,blue lighning will strike the water.When you go inside the water,you will be in the Glowstone Ocean dimension.