The Aquatic Abyss mod adds life, both mythical and real, to the oceans of Minecraft! This mod adds many species of fish, seahorses, and other creatures, as well as mythical creatures like the sea serpent. Along with that, this mod also adds seaweed to the ocean to make the environment more lively. More features to come soon!
Requires Forge and the AnimationAPI.
More information on the forum page here.