All the bee books say that the hive should be at a slight slant to allow water to drain out and not accumulate in the bottom of the hive.
It seems to me with an open Screened Bottom Board and a slatted rack that the slant is no longer necessary. I didn't slant either hive last year, but want to do everything better this year, so if I should be pushing a shim under the back of my hives, please let me know.
Linda T trying to be a better Atlanta beekeeper