Use the left and right arrow keys or click the arrows on the bottom to rotate the fish. You have to click the smiley phone in the corner for the arrows to appear. Avoid the orange circles. Click the circular arrow in the top right corner to restart (with the same difficulty you just played with).
If you click the restart button more than once the fish will break. It also might break even if you have only clicked restart once. Below are the notes of the D harmonic minor scale. D E F G A B♭ C# D C# B♭ A G F E D