A customer called me up the other day about this and I thought it was a really great idea just to make a short blog post about it.
He owned a Fluval Edge and wanted some plants which were small enough to not dominate his tank but easy enough not to cause him too many problems. Lighting is limited. So my top 3 plants for it are:
Echinodorus magdalensis
Micromanthemum umbrosum
Staurogyne rubescens
All these will not only look great but are relatively easy. Make sure you use some Neutro T fertiliser and you'll have a lovely looking tank in no time!