I think you can get away with anubias, as was listed earlier. If you're coming in around 1 watt/ gallon, anubias and java fern will get along well. If you've got around 2 watt/ gallon or better, your options open up a bit more. Jungle val looks great and grows well with descent lighting (but it grows quite tall, so you need to keep it in check). Red ludwigia does pretty well. Also, you can pick up a bag of flourite from the store and sprinkle it into your tank. It will help you out and mixes well with natural gravel.
