Micranthemum 'Monte Carlo' - New Large Pearl Grass Live Aquarium Plants Micranthemum Monte-Carlo can be compared with the very popular Hemianthus Calitrichoides, in that the leaves look very similar and it carpets very well too. Micranthemum Monte-Carlo leaves are slightly bigger, ranging from 5mm-10mm. It is a bright shade of green and is a wonderful plant to carpet. A great alternative to HC. It does not need as much light as HC and is considered slightly easier to grow. Good levels of CO2 and high light will ensure this plant does well.