Great game. I like especially the option to increase or slow down the speed (: The problem is that I almost can't see my score, damage and speed, because it's too dark. You can change the color, but maybe you would like to show it as a visual diagram...

Very nice game, but I'm only one person... You may want to add an option to choose the number of players. And why do the fish swim only in one direction? Make them swim randomly!