Where to place frag

I just take my pocket knife and stab it around the base of the mushroom and cut a peice of the rock out with the mushroom on it then take my dremel and shape the rock to fit where I want it in my tank. Most rock's are easy to cut. If they are attached to a flat part of the rock you can take a razor knife and just slice em off the rock and take an empty beverage (plastic) bottle and set it in the tank on the bottom with some small rubble peices and in a week or so they attach themselves to the rubble then move em where ya want. Theres just to many ways to skin this cat. good luck