It is a layout goods to tie Riccia or Willow Moss and makes a carpet of plants on the substrate. The substrate is easily paved with the flat shape Riccia Stone. The flat shape is easy to spread and it matches on substrate.
The NEW Nature Aquarium Goods Riccia stone has more variety in sizes (S, M, L size mixed, 2 to 7cm), so you can easily place Riccia even at the edge of rocks and intricate places by using smaller size stones.