Whole House Water Filter/softener

Anybody have a whole house water filter and softener system (combined or 2 tank) recommendations?

With my limited knowledge my requirements I would prefer include: 1. Non electric (I want to be able to use when the power goes out which we all know happens way to often) 2. Least amount of maintenance frequency and cost. I don’t want to have to schedule a a special company every-time and prefer to do my own routine maintenance 3. Equipment located outside if possible

We already have an under sink reverse osmosis system for drinking water so not interested in smaller systems.

I will also take insight into brands/equipment anybody doesn’t recommend.

I know this groups teases Houston transplants but coming from the Midwest the water hardness is another animal here that I need to tame.