Change 2/3 to 6/9 and compare to 4/9 and decide

As a Tumblr user myself, their algorithm suggest that the biggest fan is the one who often reblogs or likes you post. Your avid follower.

You can share your YouTube videos on your social media accounts - Facebook, Twitter, Google Plus or you can even Pin it. Through this way, more people are able to see the video you made the more chances they are to leave a comment.