It appears in ACO videos that the rack stands that were built for use in the store do not support the aquariums across their length, at all. It appears that they are only supported on the ends. Do I perceive correctly? Another thing I have noticed about my own aquarium is that it does not fully touch it's stand along the length. I have also noticed this on aquariums at LFS. There is indeed a gap there. I wrote to Aqueon manufacturing about this detail, and they confirmed that aquariums are designed and built with a certain amount of arch along their length, and that virtually all of the weight is actually distributed at the corners. I'm no physicist, but considering the impressive mass density of a full aquarium, and the fragility (and potential dangers of) glass, this design and construction aspect of aquariums is very, very surprising to me. I hope someone at ACO will comment on this. If those racks leave the aquariums completely unsupported along their length, I think this would be a rather shocking revelation to many aquarists, and that they would be very interested in learning more about it.