Ugh! No I didn't do a shelf the whole way around! I wish I would have. I have a shelf on my shallow end for the toads and birds to get in and out. I have another shelf down by my deep end but it's probably a foot and a half deep. I have both of those shelves covered in rocks. I guess it's not too late to add that little ledge all the way around though. I'd have to let my water evaporate a few inches and pull back my liner.