Well I tore into the wall a little bit in the garage tonight to see what i was dealing with. I had figured on the Sill plate being on the cement floor of the garage, but no, what we have is a large 6x6 beam on the floor, then the decking material for the bedroom is on top of that, then the sill plate. Only issue i see is that the decking material does not come all the way flush to the edge of the beam and sill plate, it is slightly recessed. Seeing as I am beefing up the cripples under the Window sill and the window sill will bear a lot of load of the aquarium, I am mildly concerned about this half inch gap, is it anything to worry about? Pic isnt very good.