Theme preset to not identify links

The problem is that on my website Fish Tank Supplies any and all outgoing links have nothing identifying themselves as a link unless you mouse over the link. In WP admin the text is underlined and blue but when published I think the theme strips the code off. My question is what file is in charge of font protocol and how should I go about editing it to show viewers that the text is a outgoing link with out having to mouse over the text to see that it is underlined.