Check out Underwater Coral Reef Habitat Ocean V3 Low-poly 3D model on CGTrader for $149. High-quality mesh by djeymax: 6391370 polys, 5303056 vertices. Animated, PBR, Textured.
MAX (Autodesk 3ds Max, filesize: 51.8 MB), OBJ (OBJ, filesize: 170 MB), FBX (Autodesk FBX, filesize: 69.7 MB), TEXTURES (Textures, filesize: 402 MB)