Vallisneria
Fast growing aquatic ribbon plant. Creates a rolling prairie effect. Suitable for beginners, does not require CO2.
Detailed explanation
Vallisneria (spiralis, Americana, gigantea, nana) is one of the easiest plants. It grows quickly, sending out stolons that colonise the bottom.
V. spiralis is the most common. V. nana remains lower. V. americana/gigantea has leaves that reach the surface even in 60 cm aquariums.
Tolerates a wide range of parameters: pH 6.5-8.0, moderate light, no CO2. It also grows well in aquariums with African cichlids (hard, alkaline water).
Does not tolerate Excel (glutaraldehyde): it melts and dies. Incompatible with glutaraldehyde-based anti-algae treatments.