Reduce paragraph spacing

I'm using the free Catch Box version 1.7.2.2 and I'm familiar with adding custom styles via the Themes Options page.  Does anyone know a way to reduce the spacing between paragraphs in a blog post? I've noticed that when using the WYSIWYG editor that the source copy appears to be formatted like below so are there some margin size, width or height values I can input to override the defaults and reduce the spacing between paragraphs? <p>Paragraph 1</p> <p>Paragraph 2</p>