First cut the mushroom into four seperate parts as shown on the left. The mushroom should be cut where the lines are and the base should still be attached to each mushroom piece. It is very important to keep part of the base on the mushroom. Now you should have four seperate pieces like the picture on the right. You should now take a string and attach each piece to a rock fragment so that it can regrow. Make sure there is slight current to keep the mushroom clean but not too much that its flows away off the rock. After about a week or so the new mushroom should be attached to the rock and begin to regrow.