Please help size water softener / carbon filter
I'm currently completing a new home, should be ready in about 4 weeks. We are on city water (Houston, TX). We've stubbed up for a water softener in a closet accessible from the garage. I'd also like to do a whole house carbon filter (yes, I know there are those that advise against it). The house is 4,100 sq ft, 4 full bathes, and it's my wife and I plus our son - and we're expecting our second child so I'd like to size for four (4) people. I also am picky about losing water pressure in the house (showers). Our master bath has a 12" rain head plus standard shower head but no body sprayers, we have a large soaking tub but no jets. Kids will share a jack/jill bathroom - the other shower is a guest and the last shower is upstairs (not used frequently).
I filled a 4.5 gallon bucket in 32 seconds using my master tub. I also had a water test done, here are the results:
Copper = 0 ppm
Total Chlorine = 1.5 ppm
Nitrates = 0
Nitrite = 0
Alkalinity = 100
Hardness = 9 GPG
pH = 7.0
TDS(Total Dissolved Solids) = 297ppm
Iron = 0
Any recommendations on sizing and brand / model of system would be much appreciated!