Hello,

I'm trying to find the movie i watched long time ago i can't remember the name but i can remember what the movie was about.

It was about Aliens who came to earth, they've sent message to the humans and waited for reply( i think).
The humans couldn't decode the message, they feared that the Aliens are hostile, and started an attack on them.
Before it was to late to cancel the attack they figured it out that the message was recorded under water, and that the aliens come in peace, the attack goes on, the aliens respond destroying the bigger cities, movie ends .
(if i remember anything more i'll update my post).

I've had this movie in my head for weeks now, and i still can't remember its name, any help would be appreciated.
~regards.