A highly interesting and recommendable ground-covering plant that's still a rarity. This plant is also known under the name "New Large Pearl Grass," and in South America as "Bacopita." It looks like a larger version of Hemianthus callitrichoides, but it is also somewhat similar to "standard" Micranthemum umbrosum. It grows flat on the ground, forming a compact mat. The roundish leaves are a bit smaller and of a darker green than those of M. umbrosum. When planted in an elevated place, loose shoots will bow to the ground. This Micranthemum is easier in cultivation than Hemianthus callitrichoides.
You are buying one pot that will cover approx a 4" by 4" area. If you plant it in the pot, it will cover a 2" by 2" area.
Potted plants are better to start with then "bunched" plants as they have their entire root system intact, which makes them less likely to go into shock when transplanted in your aquarium.
Potted plants are started in rock wool. To plant remove as much rock wool as possible. Most of the rock wool will pull off. If you have any left and want it off, shake the plants gently by holding it by the roots and shaking in water. Leaving some rock wool will help anchor the plant in your substrate.
Separate the plant into 1/8" pieces with roots and plant 1/8" to 1/4" apart in your substrate. This will leave room for the plant to propagate and spread. If you want instant gratification, you can plant closer. It will take more plant to fill in the area you want to cover when planting closer.
Only plant the root in your substrate, not any of the plant itself or this can cause melting or shock, for more information on planting and caring for your plants, please go here.