Rotala wallichii

Rotala wallichii is an elegant stem plant originating from soft, slightly acidic waters in South-Eastern Asia. Its inflorescence has bright purple flowers. Even though it is not quite easy in cultivation it is a highly popular plant.

R. wallichii needs lots of light, CO2 fertilisation and a well-balanced supply of nutrients to grow well. The light intensity should at least be 0.5 watts per litre in order for it to attain intensive colours and to support growth. A good supply of CO2, either with bio CO2 or a system using pressure bottles is indispensable. Rotala wallichii grows best if the nitrate level never falls to zero but does not exceed 10 to 15 mg per litre either. A high phosphate content of 1-2 mg per litre is preferred, as well as a good supply of iron and micronutrients.
Under optimal growth conditions this plant rewards its keeper with stunning colours, ranging from intense pink over orange to deep red foliage with a diameter of 2 cm and more.

This Rotala species forms opulent finely-structured groups growing upwards. Those plant parts closest to the surface develop the most intensive colours and throw a large number of lateral shoots. If R. wallichii grows too large for your tank design you can just cut off the uppermost part and re-plant it in the substrate. Propagation is done by cuttings of top and lateral shoots. They grow new roots very fast if re-planted in the substrate and start growing again.

Colourful R. wallichii is used in Nature Aquaria and in Dutch-style tanks. It is a great red accent plant for the middle- or background of an aquarium. In order to get the best effect, three to five stems should be planted at a time so they grow to form beautifully dense groups.