I'm getting confusing answers regarding the sizing of the water softener I would like to purchase. According to most calculations a Fleck 5600 sxt 32,000 grain / 1 cu. foot model will give me lots of capacity but there seems to be a tendency to upsize to a 48,000 / 1.5 cu. foot model. I'm not concerned about the added cost just efficiency.

Here's my requirements, 2 middle aged adults (no kids living with us now), 1 bath/shower, 2 toilets, washer, dishwasher - all high efficiency. Checked the water bills and our average total usage is around 100 gal per day. Water is pretty hard @ 19 gpg but there’s no iron and we’re on a municipal well system that serves about 1500 hundred people hence the water is treated with chlorine. According to my calculations
I‘m getting about 10 gpm flow rate. Also the outdoor connections will be bypassed.

Any Ideas?