PCR faint bands under UV light - (Feb/20/2008 )
I hope you have some positive controls for your PCR just to find out if it is your PCR technique that is not working or is it some problem with the gel. Try increasing EtBr in your gel or make new EtBr. Or it could be that your stuff is just leaking out of the wells. As someone suggested, tape two wells together to make a large one and try adding more glycerol to your sample so that it doesn't float out. But first figure out if the PCR is the issue by using appropriate controls.