I downloaded the source files to try and follow along with your water shader tutorial, but I don't have some of the image textures you used, and many of the surfaces in your files are just displayed pink. Is there something I might be doing wrong?
Try this: With the file open, go to File > External Data > Find Missing Files and navigate to the tex folder that's included with the Project Source Files download. When in that folder, click "Find Missing Files" and all your textures should be sourced correctly - no pink.