Twin-tank softener · Fleck

Fleck 9100 SXT 48,000-Grain Twin-Tank Water Softener

48,000-grain softener for up to 4 people at 15 gpg

Updated October 2026

Quick verdict

A sensible twin-tank softener for up to 4 people on 15 gpg water.

Strength
48,000-grain rating.
Trade-off
Service flow not stated.
Right buyer
Up to 4 people on 15 gpg water.
Grain capacity (maker)
48,000 grains
Resin volume
1.5 cu ft
Control valve
Fleck 9100
Tank size
10x54
Dimensions (seller)
10 x 10 x 54 inches
Product weight
95 lb
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What it does for your water

The Fleck 9100 SXT 48,000-Grain Twin-Tank Water Softener is a twin-tank softener rated at 48,000 grains on a Fleck 9100 control valve.

Run at an efficient salt setting, its 1.5 cu ft of resin gives about 36,000 grains per regeneration rather than the full rating: enough for up to 4 people on 15 grains-per-gallon water regenerating weekly, or 2 on 25 grains per gallon. Check it against your hardness.

The second tank is the point: the house stays on soft water during every regeneration, which suits large or round-the-clock households.

The Fleck 9100 head is one of the most widely serviced valves; seal kits, pistons, boards and meters that name it are in the valve parts lookup.

The listing also gives tank 10x54; model 9100 SXT; resin 1.5 cu ft; valve Fleck 9100.

The listing gives dimensions of 10 x 10 x 54 inches, a shipping weight of 95 lb and complete system in the box.

Is it the right unit for your house?

Choose it when

  • Up to 4 people on 15 gpg water
  • Replacing an older softener

Pass on it when

  • More than 2 people on 25 gpg water
  • Iron above about 5 ppm without an iron filter

Where it wins and where it loses

Wins

  • 48,000-grain rating
  • Fleck 9100 valve
  • 1.5 cu ft of resin

Loses

  • Service flow not stated
  • Requires a drain line and power
  • Adds sodium to softened water (potassium chloride avoids it)

Limits to know about

  • Figures are the maker's or seller's own; check fit and capacity against your water test and your equipment's manual.

Maker's figures

Every figure below comes from the source shown in brackets. Where the maker doesn't state something, we say so instead of estimating.

Model number9100 SXTRetailer
Product weight95 lbRetailer
Dimensions (seller)10 x 10 x 54 inchesRetailer
Grain capacity (maker)48,000 grainsRetailer
Resin volume1.5 cu ftRetailer
Control valveFleck 9100Retailer
Tank size10x54Retailer

Other water softeners in the catalog

Every water softeners on one grid · All Fleck units we cover

Final verdict

A sensible twin-tank softener for up to 4 people on 15 gpg water.

Where to buy

Our links open this exact model's product page. Prices and stock change; check what's included before you order.

Prices change often; the button shows today's price.

Each button opens this exact model. We may earn a commission on tracked links; it never changes what we publish. Disclosure

Questions buyers ask

How many people is the Fleck 9100 SXT 48,000-Grain Twin-Tank Water Softener for?
At an efficient salt setting it delivers about 36,000 grains between regenerations: up to 4 on 15 gpg water, or 2 on 25 gpg, regenerating weekly. Iron adds load: each ppm counts as about 4 gpg.