This is a paid asset, but now you can download Schooling fish Blue and Yellow Tangs Free.
Detail this asset from Unity Store: Original Link
Schooling fish Blue and Yellow Tangs v1.0
“If possible, please buy the package to support the developer”
Schooling of Coral fish animated in a loop
The school of fish contains 30 fish:
20 fish Blue Tang
10 fish Yellow Tang
All Fish Animated in the loop duration 30 sec.
Fish Blue Tang:
Verts:597, Edges: 1175, Tris: 1160
Fish Yellow Tang:
Verts:501, Edges: 999, Tris: 998
All Verts: 16950
All Edges: 33490
All Tris: 33180