Micranthemum umbrosum is an exquisite aquarium plant originally from the US. Its round leaflets grow to around 0.5 cm and are a brilliant light green. This is a typical light-hungry plant and does not tolerate higher temperatures. As with Hemianthus micranthemoides, these plants are easy to keep in shape with a sharp pair of scissors. Pearl grass is suitable for Nano Cubes, particularly if you are running your miniature aquarium without a heater.