Your aim is to guide tadpole to his home and avoid all obstacles on the way. Hold LEFT MOUSE BUTTON to swim up, release the button to swim down. Avoid hitting Rocks, Algae and Waterbugs. Be sure to collect those bubbles, they will save you life many times.
You have to form color lines using boxes that change color every time you select a line. This boxes change from red to yellow, to green and then back to red.