Hi, thanks for the review. I wouldn't mind if you rated the game on this site.
I always (almost) catch the fish with the maximum reward. There is no random, you can hover the fish icon with cursor and see if it is real or not.
If you are playing on your phone, I have enlarged the icons for convenience. You need to press your finger on the screen anywhere where there is no fish. Then, without lifting your finger from the screen, aim at the fish icons. Release your finger from the screen when you reach the desired icon.