This Rhodactus sp. Mushroom grows to be 4-5" and then destroys itself into 3-4 smaller mushrooms. I say destroys because it looks like it exploded and leaves pieces of itself all over the bottom of the glass in it's holding tank. But since we purchased a single one last year it's turned itself into 30 or more mushrooms. It's become a local favorite because of it's blinding green color.