Guppy Grass, Najas Grass (Najas Guadalupensis) is very easy to grow and is a hardy plant. You can just let this plant float in your tank and it will overtake your tank in matter of weeks. You can also plant it in the back of the aquarium to create a wall of foliage. 
Najas grass efficiently pulls nitrate from the water column, so it can be used in heavily stocked tanks to keep nitrate levels lower. It is a well know plant for hobbyist breeding livebearers. This plant will provide a good habitat for young fish, where they can hide, forage and stay safe from other predatory fish. 

Purchase Size: one bunch (6-8 stems), 6-8” long strands