## Trying to correctly size a softener

Hello Everyone,

I have rummaged over a lot of information over the last week or so trying to understand how water softeners work and how to correctly size one.

I almost got tricked by the Kinetico sales people with their efficiency claims, but thanks to the wealth of information that Gary posted on his website (Thanks Gary!) I managed to realize what the marketing spin was.

Now I have used the calculator from Gary's website to size the softener, but I am not 100% sure I understand a couple of aspects and I would appreciate it if somebody could clarify it for me.

Here are the parameters that I am using:

Water Hardness: 15 gpg (phoned the City and they said it is average 15, but that it varies between 12 and 21). Kinetico sales person correctly identified measured it at 14 gpg, Culligan sales person said it was 30 gpg

Water usage: There is between 6 and 7 of us in the house, and I averaged our usage based on the water bills over a 1 year period at ~ 500 gallons / day. So the numbers I plugged into the calculator were 7 person @ 70 gal / day usage.

The results of the calculations:
Daily Grains of Capacity: 7,350
Total Grains of Capacity: 58,800
Minimum cuft size: 3

Now... If I correctly interpret the numbers in the generated table:
Scenario A: 8 days between regenerations (recommended?)
Pounds of salt Per Cubic Foot of Resin: 6
Salt dose (total lbs): 18
Salt Dose Capacity: 60,000
Grains of Capacity PER lb of salt (salt efficiency): 3,333
Gallons between regenerations: 4,000

Scenario B: 5 days between regenerations
Pounds of salt Per Cubic Foot of Resin: 3
Salt dose (total lbs): 9
Salt Dose Capacity: 38,400
Grains of Capacity PER lb of salt (salt efficiency): 4,267
Gallons between regenerations: 2,560

1. Do I understand correctly that the preferred / recommended size for my house would be a 60k grains softener with a 3 cuft resin tank (scenario A)?

2. When I look at Grains of Capacity PER lb of salt (salt efficiency): 4,267 for Scenario B, I see that the salt efficiency for this scenario is better than for scenario A. Would it not make more sense then to go with a 40k grains tank and regenerate every 5 days?

3. One of the independent contractors I am talking to locally is recommending to me one of the following three options:

a) 40k Grains 1 cuft resin softener with Fleck 5600 SXT head (cheapest solution) - regenerates every 3.5 days

b) 40k Grains 1 cuft resin softener with Clack WS-1 head - regenerates every 3.5 days

c) 50k Grains 1.7 cuft resin softener with Clack WS-1 head - regenerates every 7 days

Options b) and c) he is offering for the same price

Is any of these systems suitable for my needs? I am inclined to go with option c). Any advice?

4. Our City water is pretty heavily chlorinated and I am thinking of adding either a timed (Fleck timer head) 1 cuft Activated Carbon filter or a simple 20" AC cartridge filter before the softener.
a) How are these filters going to affect my SFR?

b) Any information on how to correctly size the Carbon filter?

5. I noticed on Gary's website that are several options when it comes to resins. Is there a significant difference between the different brand / types of resin used?

What I am trying to do is to minimize the water and salt usage to the best possible level given my parameters.