Your pic looks like the same ones I got for my tank a few months ago. Just give them a chance and they'll spread, especially now that the old rock is crowded. My biggest mushroom (about 5 - 6" diameter) is just about through "migrating" to the rock next door. As soon as it's out of the way another starts growing from the little piece of tissue it leaves behind. Soon you'll have enough to trade - notice my signature line?