Can anyone suggest a plant with a form similar to Limnophila aquatica (Ambulia), with similar requirements, that is not invasive? My ambulia has not grown full and fluffy (probably because some floating plants block the light) but does send runners all over the tank, and pops up where least wanted. Thanks. Greg. Tong San Francisco, CA, USA gtong at sirius_com "Every infinity is composed of only two halves."