The Amazon Sword is a long known, time-tested aquarium plant from tropical South America. It differs from E. grisebachii 'Bleherae' by considerably narrower leaves. This Echinodorus wild type is quite undemanding, however medium light intensity and a nutrient-rich substrate are recommendable.
Echinodorus 'Amazonicus' develops a large, conspicuous rosette with countless leaves. It is especially recommended for large tanks with e.g. Discus or angelfish (Pterophyllum). The latter often use the swordplant leaves as spawning ground.