New pool owner: loud pump?

[nojjynb]

Hi, I just bought a house that has a pool. I have never owned a pool. When I initially hooked everything up, the pump wouldn't start. I took apart the impeller, and found that it wouldn't turn. A light twist with a socket wrench got it turning, and now it spins when powered on. It pumps water fine now, but it seems to be very loud compared to what I was expecting.

I've uploaded a video of the pump running, with talking prior to starting the pump to help determine volume.
http://www.youtube.com/watch?v=x3HReYEnrdU

Notice that the connection between the impeller and the filter tank is a little offset and so it is leaking. Could this be causing the loudness?

Also, if this seems normal, how often should I run the pump? I don't want to have that going all the time and annoy my neighbors!