Looks good. You don't need a background really. Its just a preference. I only have one tank with background. As long as your pets are cared for and protected from bad conditions that's what is important. Be sure to get a liquid test tube kit before your background!!
Lol, I don't have background for any of my tanks. My dad asks me why I don't buy them, then I ask him if he would like to buy some for me. That sure shut him up. XD
Thats awesome very bright and colourful! I have that driftwood ornament to, my mollies love it. What do your guppies think of it?
Backgrounds on fish tanks... I've neglected to get one because I dont like many of them that are sold at my lfs, and my walls are a nice blue with a little bit of a darker blue swirled on top so it provides a nice backdrop itself