A great soothing effect, the layered ripples in this water effect image add realism to the finished image. Colourise to green or red for a great sludge or lava-style look.
Open up a new image with a white background.
Press D on your keyboard then go to Filter > Render > Clouds.
Next go to Filter > Blur > Radial Blur and change the Amount to 38, and the Blur Method to Spin.
Then go to Filter > Blur > Gaussian Blur and change the Radius to 2.
Go to Filter > Sketch > Bas Relief and choose Detail, 13 and Smoothness 10.
Now, Filter > Sketch > Chrome and pick Detail 5 and Smoothness 2.
Finally, colourise and save!