Hondatech,
Read the rather lengthy post on the "Super Algae Scrubers" these are very efficient as to maintaining water parameters. Noise level is higher than canister and many other filters as you have the sound of "Falling" water but this can be dampened to some degree.
I built mine in a rubbermaid type plastic bin/box and it is pretty quiet w/ the top on. I have like NO algae growing in the tank, I never have to scrape the inside of the glass, the glass never feels "Slimey / slippery all parmaters are fine.. well NitrAtes are at 20 ppm but that is still fine. I have 2 cats, a redtail cat and what I "Think" is an well not sure.. both large over 10 inches and both messy eaters! so I am happy. I guess if you house your Algae scrubber in the tank stand and close it off the noise would be minimal.
Good luck