It's hard to recommend the right plants without knowledge of how much/what type of lighting you have over your tank. There are many types of low maintenance plants, but they have different lighting needs.
Assuming you have a low light tank, start with java ferns, anubias, hygro polysperma, java moss. Crypts will work as well but need more advanced care and decent substrate.
Everything already said and water sprite in its submerged growth form. At first it might grow slow, become covered with algae, and loose old leaves but eventually it takes off and makes a great plant.