A couple of issues that would make the game a much better experience:
1 - Make the tank more distinctive in its direction, the little green dot was easy to miss.
2 - Remove the instructions when the game starts
3 - Add WASD also to controls had to play with arms crossed because of the location of my arrow keys.
4 - Does a player really need to know the time to a 1000th of a sec?
But I enjoyed the game still.