No longer see fishes - only dolphins

When the Aqua version was first released I had fish and dolphins in the sea. Then an update to the Aqua version came out 1.4.1 or something like that and I have never seen the smaller fishes in my world since however I do still have dolphins.  I had reported this before via searching for this topic and tagging my issue on to another issue but their issue was Java based and not Windows and no-one has answered my comment on how to fix this in Windows 10, hence why I am creating a new issue.  Is there something I need to do to rectify this.  This problem has not resolved with the latest 1.5 version either so I would appreciate assistance.  Thanks