There are plenty of bottom dwelling fish but they have a much bigger bioload and depending on species may disturb small ground plants, especially before they become established.
It is a common misconception that bottom-dwelling fish 'clean' the bottoms of tanks. Sure, they may eat leftover food but they'll also produce waste, that can lead to algae issues if your maintenance isn't spot on.
Corydorus and small Botia may be worth a look. Both need to be kept in groups no smaller than six for them to thrive.