Rotala Rotundifolia trimmings. 2 stems for aed 1. It is tolerant of a wide range of water parameters and is an easy plant to grow; it will even do well in aquariums without carbon dioxide injection after a period of acclimatisation. However, with sufficient light and CO2 it will grow with better density and colouration. As stem plants they will grow continuously towards the light and will reach the top of even high aquariums. If allowed to reach the water surface, it will eventually break through the surface and grow submerged leaves and flowers. If stems are planted in a high light aquarium with plenty of space around them, they will grow downwards and creep along the bottom. If planted in a more crowded area they will grow more vertically. The plant will branch more when in rapid growth mode and will grow more vertically with less branching when conditions are low (either low CO2 or low nutrients).