Measure 8 to 10 inches down from the top of the water jar on the side you want to be the back of the fountain. Mark the location with masking tape formed into an X.
Set the jar on a stable surface. Wear protective goggles, as clay shards are sharp. Drill a one-inch hole through the masking tape and jar using a ceramic bit.
Fill the jar with pebbles or rocks until the rock level is just beneath the hole. Set a 150-GPH water pump in the jug on top of the rocks.
Attach a length of clear, stiff tubing, 1/2-inch in diameter, to the spout on the water pump. Use a piece of tubing that reaches to the rim of the jug.
Thread the cord of the pump through the hole you drilled in the jug. Adjust the clear tubing so it is centered in the jar opening.
Set the jug in a metal or plastic decorative tub. Fill the tub with decorative stones or plants.
Fill the jug with water and plug in the pump. While most of the water will stay within the water jug, some splashing may occur.