Final rendition looks odd

Support Modeling
1

After solving problems with my water, I started another tutorialand all went fine up and untill very

when tutor adds another plane to cause back edges of cube to disappear. After adding additional plane, my result looks like this:

paprikas.png960×540 121 KB


Any idea why there is a difference between tutorial and my final result?

thanks :slight_smile:paprike_voda.blend (676 KB)