Have any more info on the tank? Size, livestock, equipment? There is really no set rule of what you need in a sump. It is really just based on what you want to do with the tank. If you are just looking for a little extra water volume, a place for media, and some extra biological filtration, I would personally just do one baffle, and put your LR and media bag in one side, and then the return pump in the other being that it is only a 10gal.