A medium-sized Cryptocoryne, can be grown in the middle of the aquarium, has spear-shaped green leaves.
The picture is of our actual stock that we have cultivated.
We keep all of our Crypts in a deep bed of sand/gravel and laterite and have no fish or snails in with them, just Cherry shrimp to keep them clean and healthy!

You get a good clump with a lot more than one plant, usually 3-4