I want to plant Hemianthus callitrichoides as a foreground plant in my high-tech (55 gal, CO2, ferts, light 2 watt/gal). No one sells them here so am buying from reputable online store. How many of these should I buy? Do they come as individual plantlets or as a bunch? Can they be broken up and planted around the aquarium and allowed to spread and cover? Any help on this is greatly appreciated. Thanks.

they usually come in small patches x by x, or in the little container pots. It really depends on how much you would like to grow and how fast. Most people typically plant little pieces every few inches in the area they want to fill in. Be warned that HC is difficult to get started, it often floats away. If you break it up its going to be somewhat difficult to handle, long tweezers are your best bet.

I would grow them emmersed first. Then take samples of those to plant in your main aquarium. That way you have a continuous supply of HC for making mistakes in the learning process.