I usually try to use the same color value thread on top and bottom. Plus I find though while quilting I may see the little dot of the thread from below, once I've washed the quilt, they seem to disappear. Most times I rarely have issues with tension. When I ordered my Innova I ordered their upgraded upper tension system and I've never looked back. These days I'm trying out different types of threads so worried I may have issues but the last quilt I used a 70wt polyester on top and a cotton 50wt in the bobbin and was pleasantly surprised I didn't have tension issue. Not one thread break either.