An aquatic animal such as coral is propagated on a base. The base has a top portion with a groove located therein. The groove has converging side walls. The groove intersects a depression that extends from the top portion to a bottom portion of the base. The depression has converging sides. An animal fragment is secured to the base by locating it in the groove, or alternatively in the groove and the depression. Water flow across the base may cause the fragment to move inside of the groove, wherein the fragment will sink down and become wedged in place, further securing or coupling the fragment to the base. The coral then grows and adheres itself to the base.