Place a small plastic pond liner in the bottom of a large pot. Alternatively, you can use an urn or a trough. Buy a liner that's big enough to come up the sides of the container.
Cut the liner to fit the pot, using garden scissors. None of the liner should be visible when the water feature is finished.
Connect the end of 25-inch water-pump hose to the output spout of a pond pump.
Place the pump in the bottom of the large pot. Position its flex so that it comes over the back rim of the pot.
Position two bricks inside the pot, one on each side of the pump. The bricks should be slightly taller than the pump.
Fill the pot with water, up to the top of the liner.
Place a plastic grill with slats big enough for the hose to fit through on top of the bricks, and pull the hose through. Make sure the grill fits snugly inside the large pot.
Position a water-feature urn on top of the grill. The urn you use should have a drainage hole on the bottom. Push the hose through the hole.
Place pebbles, shells or marbles inside the urn and on the top of the grill, hiding the liner and the pump.
Place plants behind the water feature to disguise the flex. Turn on the pump.