overhead water tank 3D model is available on CGTrader for $2. Original author: CraftedIn3D. Specs: 46952 polys, 23613 verts.
SKP (Sketchup, filesize: 17 MB), BLEND (Blender, filesize: 6.21 MB), OBJ (OBJ, filesize: 6.07 MB), FBX (Autodesk FBX, filesize: 13.1 MB), MAX (Autodesk 3ds Max, filesize: 6.75 MB), GLTF (glTF, filesize: 15.1 MB), TEXTURES (Textures, filesize: 13.9 MB), 3DS (3D Studio, filesize: 2.35 MB), DXF (DXF, filesize: 17.4 MB), DAE (Collada, filesize: 5.38 MB), PLY (Ply, filesize: 7.2 MB), STL (Stereolithography, filesize: 11.5 MB)