Small foreground plants for aquariums are in short supply, but Echinodorus tenellus from North America is one of the best. The runners spread round the aquarium. A true "lawn'' effect appr. 5-10 cm tall is only achieved at high light intensities, so you must make sure larger plants do not overshadow the plant. Plant individual plants a couple of centimetres apart (easiest with tweezers). A nutritious bottom promotes growth.