About your wood 8O Typically newly placed wood in an aquarium that hasn't been boiled or soaked leaks tannins (sp?) into the water. Naturally released color from your drift wood. Typically this makes the water appear to look like "tea". In my experience however, this isn't accompanied with cloudiness. If your tank is fairly new, I would guess that you have 2 things going on, #1 a bacterial bloom because of the instabilty of your new tank which should disappear over time (A white or fant green cloudiness)... mixed with #2 leeching colors from your wood creating a "cloudy tea" consistancy.
There isn't much you can do for either, the cloudiness from the bacterial bloom will disappear on its own and you should see it diminish from your weekly
PWC, the brown color you are getting from the drift wood can also be taken care of. If you have a pot large enough, take the wood out and boil it changing the water until it boils clear, then put it back in your tank.
I will mention that neither of these conditions should be harmful to your fish, only effect the athestic value of the tank.
About the size of your filter. Bacteria that is necessary for the tank is on all components of your aquarium including, filter, bio-wheel (if you have one), gravel, plants, and decoration. I don't see how a powerful filter can impede the growth and development of micro-organizms. The only downfall for a serverly over powered filter is the currents that you would have in the aquarium from the discharge which some of your fish may not like and could stress them. If you have a control to reduce the flow on the filter I would do that.
Again, what are your water perameters, and what is the
WPG the filter is pumping in relation to your aquarium?