I could never have imagine this game, so hats off to you for that. The only suggestion I could make is it might be interesting if the player had more control over the flop. Perhaps rather than a binary flop right or left, there could be a flop axis controlled by the mouse or analog stick? Perhaps 3 dimensions of flopping? I'm not sure... Though the game certainly gave me a good laugh.
Analog controls could be interesting. Didn't have time to try them. There is some control, though. The angular force is applied while the key is pressed, so you can have a weaker flop if you tap the key quickly. In order to allow the fish to flip high enough to get over things, though, I had to make the velocity pretty high, so the window is REALLY small.