The wood bits look nice, but I feel that the arrangement is a bit contrived. If you are going to lay the tank out to rule of thirds then you want to have focal points at intersecting thirds, at the moment there isn't really anything on an intersecting third and the whole is weighted to the middle third.
I would think about removing the right most bit, then move the rest towards the right so the third line on the right runs up the left side of the heavy bit that is in the front of the others.