Ambulia (Limnophila indica). Stem plant. It was grown in the aquarium.
This Limnophila is an undemanding, decorative, fine-leaved stem plant from which dense bushes in the middle or background of a layout can be created quickly. The leaves are light green.
3x 3-4 in stems for $5.
Guppy Grass (Najas Guadalupensis)
This plant can thrive in low-light and low-tech setups and will grow into a large mass that can be easily pruned. Guppy Grass can be planted, but it is typically best left floating in a free-form mass.
Zip bag - $4.
Duckweed
This is a floating plant. Green on top and red-ish on the bottom. Easy.