For the pier decor, how about using malaysian driftwood? I don't know the availbility in your area, but when on my hunt for driftwood (at LFS), I've seen many "XL" pieces that were "logged shaped". You could even take a saw to them to finish off the ends and clean up a bit. They could look very much like pier "lumber", and, they would stand the test of time and be aquarium safe. It's not the cheapest route, but likely a one time cost.