Header issue

Hello,

When viewing my main page, and then clicking on the “test” link with the picture of the fish, a new page comes up and I was able to eliminate the picture from posting in the header but now I am looking to see how I can completely remove the grey area that takes up most of the screen where the designer had it set up for a picture to go in. I basically want to click on any new posts and not have a header there at all. So it goes directly into the text part and not have to scroll down to view. If anyone can help solve that I would appreciate it

Thank you

The page I need help with: [log in to see the link]