I am looking at taking photos from a top down position in my tank. I currently have a Nikon D300 body and Nikkor 50mm, 24-120mm and 105mm macro lenses. I recently purchased from Avast Marine, their top-down port hole to protect my lens from water when submerging it. So my question is for my tanks (36" x 60" x 27" tall and 24" x 24" x 12" tall), which of my lenses is best used to get good photos. I tried taking a few the other night and was not impressed by any of them. If my lens selection doesn't house a great option, what others should I look at? Thanks in advance for the help.