Here is the full list of all 18 Blow & Fly achievements.
Launch a Ghostfish into the spikes.
Jump 5 times in a row without releasing the jump button.
Fall into the abyss.
Finish 15 levels within their jump limits.
Complete 5 secret levels.
Choose the third option, when confronted with an "Important Choice".
Destroy a wall.
Win a game of "Fishball".
Destroy all targets on a shooting range.
Complete "Floor is Lava" within its jump limit.
Trigger the "Laser Alarm" and still finish the level.
Find your way out of an invisible level.
Die without making a single jump on the level.
Unlock 3 new fish types.
Complete the "Trial of Cunning" without using the key.
Fly upwards faster than any space rocket in the world.
Stay airborne and avoid touching the walls for 10 seconds.
Get flushed down the toilet 35 times.