On a funny note, I figured out last night that I had my bean animal return setup wrong. I had the full siphon and open channel pipes swapped - so I was never getting flow down the full siphon pipe and was using the emergency pipe a lot. It was loud and never worked very well. By swapping the caps on top I've remedied that and was able to turn up my new pump to max and it's now dead silent! Thank goodness for Google and beananimal.com.