Direct answer: The NuGen Fusion XT manual lists six softeners sold under the Gemline name. In order of maximum rated capacity they are the cabinet XT-32C (28,000 grains), XT-48 (36,000), XT-60 (47,000), XT-70 and XT-70ER (60,000 each) and XT-90 (69,000). Each maximum comes at the highest salt dose. The model number is not the rated capacity. The XT-70ER has the same published capacity, flow and resin as the XT-70, but it is the only model with a demand-initiated-regeneration efficiency rating: 4,042 grains per pound of salt at a 9.81-pound dose. Choose by your hardness, daily water use and peak flow, not by the number on the label.
Publisher boundary: Water System Guide is an independent research publisher, not NuGen, Gemline or a dealer. Specifications come from the manufacturer’s Fusion XT manual (footer revision 5/10/2012) and the Gemline brochure (PDF created May 2023), both reviewed October 8, 2026. Where the two documents disagree, we show both rather than choosing one. Confirm the exact model and configuration in your written quote.
How do Gemline and Fusion XT model names relate?
The 2023 Gemline brochure says each Gemline softener is WQA-certified under the matching NuGen number: Gemline-32C under Fusion XT-32C, Gemline-48 under XT-48, and so on through Gemline-90 under XT-90 (brochure page 3). The brochure does not list a Gemline-70ER, but the Fusion XT manual covers the XT-70ER on its own data sheet. A Fusion XT installation may therefore carry either name on the label.
Fusion XT rated capacity, salt and flow by model
These rows come from the performance data sheets on printed pages 33 and 34 of the manual. The manual states that the softeners conform to NSF/ANSI 44 for these performance claims. Capacity is in grains of hardness at the stated pounds of salt per regeneration.
| Model | Low dose | Medium dose | High dose | Max service flow | Max drain flow | Resin | Pipe |
|---|---|---|---|---|---|---|---|
| XT-32C (cabinet) | 18,000 @ 4.5 lb | 23,000 @ 9 lb | 28,000 @ 15 lb | 16 gpm | 2.7 gpm | 1 cu ft | 1” |
| XT-48 | 23,500 @ 6 lb | 29,500 @ 11 lb | 36,000 @ 19.5 lb | 14.3 gpm | 2.7 gpm | 1.3 cu ft | 1” |
| XT-60 | 31,000 @ 8 lb | 39,000 @ 15 lb | 47,000 @ 25.5 lb | 12.5 gpm | 2.7 gpm | 1.7 cu ft | 1” |
| XT-70 | 39,000 @ 10 lb | 50,000 @ 19 lb | 60,000 @ 32 lb | 15.9 gpm | 3.2 gpm | 2.18 cu ft | 1” |
| XT-70ER | 39,000 @ 10 lb | 50,000 @ 19 lb | 60,000 @ 32 lb | 15.9 gpm | 3.2 gpm | 2.18 cu ft | 1” |
| XT-90 | 45,000 @ 11.5 lb | 58,000 @ 22 lb | 69,000 @ 37 lb | 20.2 gpm | 4.2 gpm | 2.5 cu ft | 1.25” |
All six list a 15 psi maximum pressure loss at the maximum service flow, a 40–90 psi working pressure range, 40–100°F operating temperature and a 120 V, 60 Hz electrical requirement. The manufacturer recommends pelletized sodium chloride salt.
Two patterns stand out. First, service flow does not rise with capacity: the XT-60 has the lowest listed flow (12.5 gpm) and the cabinet XT-32C one of the highest (16 gpm). Second, only the XT-90 moves to a 1¼-inch pipe size and a higher drain flow. The XT-48 vs XT-60 comparison covers the two most-searched models in more detail.
How much salt does each grain cost?
The same pattern runs through every model. Dividing rated capacity by the salt dose (our arithmetic from the table above, not a manufacturer figure) gives roughly 3,900–4,000 grains per pound at the low dose, about 2,560–2,680 at the medium dose and about 1,840–1,880 at the high dose.
| Model | Low dose | Medium dose | High dose |
|---|---|---|---|
| XT-32C | 4,000 | 2,556 | 1,867 |
| XT-48 | 3,917 | 2,682 | 1,846 |
| XT-60 | 3,875 | 2,600 | 1,843 |
| XT-70 / 70ER | 3,900 | 2,632 | 1,875 |
| XT-90 | 3,913 | 2,636 | 1,865 |
Grains per pound of salt, calculated from the manual’s rated capacity and salt dose.
The point for a buyer is simple: at the highest dose, the extra salt buys proportionally less capacity. Ask the installer which salt dose the control is programmed for. The manual says the manufacturer presets the salt dose and exchange capacity, and the installer sets hardness, day override and regeneration time (printed page 4).
XT-70 vs XT-70ER: what is the difference?
On paper, the two have identical capacity at each salt dose, flow, drain flow, resin volume, pipe size and tank size. They also share the same drive cap, piston and spacer-stack drawing (printed page 21) and blue injector (printed page 24).
The XT-70ER data sheet on printed page 34 adds what the XT-70 sheet does not have:
- Rated efficiency: 4,042 grains per pound of salt at the minimum salt dose of 9.81 pounds.
- Water consumption: 61.9 gallons per regeneration.
- A statement that it is a demand initiated regeneration (DIR) softener that complies with performance specifications intended to minimize brine and water use. Its rated capacity is not less than 3,350 grains per pound of salt, and it should not deliver more salt or run at a sustained flow greater than its rating.
- A caution that efficiencies are valid only at the stated salt dosages and maximum service flow, that the rating is a laboratory test under NSF/ANSI 44, and that operational efficiency is typically lower in a home.
If a quote lists an XT-70ER, ask the installer to confirm the control will be programmed at the rated dose. A 70ER set to the 32-pound high dose uses salt like any other softener on that setting.
Tank and brine tank dimensions: manual vs brochure
Plan the space with the installer, because the two manufacturer documents list different brine tank sizes.
| Model | Manual, media tank and valve | Manual, brine tank | 2023 brochure, system size | 2023 brochure, brine tank |
|---|---|---|---|---|
| XT-32C | Cabinet 13.5” W x 43” H x 23” D | (cabinet) | 14 x 21 x 43 | 1-piece cabinet |
| XT-48 | 10” W x 52” H | 14” x 14” x 34” | 11 x 11 x 51 | 15 x 15 x 41 |
| XT-60 | 10” W x 62” H | 14” x 14” x 34” | 11 x 11 x 61 | 15 x 15 x 41 |
| XT-70 / 70ER | 12” W x 60” H | 14” x 14” x 34” | 12 x 12 x 59 | 18 x 18 x 40 |
| XT-90 | 13” W x 62” H | 18” x 40” | 13 x 13 x 61 | 18 x 18 x 40 |
Sources: manual printed pages 33–34; brochure page 3. The brochure’s performance sheet gives the XT-32C cabinet as 14” W x 43” H x 21” D.
Why the Gemline “grains” column does not match rated capacity
The brochure’s specification table lists 32,000 grains for the Gemline-32C, 45,000 for the -48, 60,000 for the -60, 70,000 for the -70 and 90,000 for the -90. These numbers do not match the NSF/ANSI 44 rated capacities in the performance data, which top out at 28,000, 36,000, 47,000, 60,000 and 69,000 grains. The brochure does not explain the difference. Use the rated capacity at a stated salt dose for sizing. Our grain capacity guide explains why a nominal grain label and a rated capacity at a stated dose are different numbers.
Which Fusion XT size fits your home?
The manual does not include a sizing chart. Three inputs decide the size:
- Hardness in grains per gallon, from a water test. Add iron if your installer adjusts for it.
- Daily water use in gallons. A water bill or the softener’s own volume display is better than a guess.
- Peak flow: the gallons per minute your fixtures draw at the same time. Use our whole-house flow rate calculator and compare the result with the model’s maximum service flow.
Illustration only, not a recommendation: Suppose your water is 15 grains per gallon and your home uses 250 gallons a day. That is 3,750 grains a day. At the low salt dose, an XT-48 (23,500 grains) would last about six days between regenerations. An XT-60 (31,000 grains) would last about eight. The control also holds back a reserve, so the real interval is shorter. Our water softener sizing guide walks through the full method.
Put these details in the quote
- The exact model, including the “ER” suffix if quoted, and the configured salt dose.
- The brine tank and cabinet dimensions being delivered.
- The pipe size (1” or 1¼”) and the bypass and fittings being used. See our Fusion XT parts guide.
- Which warranty document applies. See our Gemline warranty guide.
Frequently asked questions
Does Fusion XT-48 mean 48,000 grains?
No. The manual’s NSF/ANSI 44 performance data rates the XT-48 at 23,500 grains at 6 pounds of salt, 29,500 at 11 pounds and 36,000 at 19.5 pounds. The Gemline brochure’s specification table lists the Gemline-48 at 45,000 grains, which also does not match the model number.
What is the difference between the Fusion XT-70 and XT-70ER?
They share the same published capacity, flow, resin volume and tank size. The XT-70ER data sheet adds a demand-initiated-regeneration efficiency rating of 4,042 grains per pound of salt at a 9.81-pound salt dose, with 61.9 gallons of water per regeneration.
Which Fusion XT model has the highest flow rate?
The XT-90, at 20.2 gallons per minute with a 1¼-inch pipe size. The XT-60 has the lowest listed service flow, at 12.5 gallons per minute.
What size brine tank comes with a Gemline softener?
The documents disagree. The 2012 Fusion XT manual lists a 14 x 14 x 34-inch brine tank for the XT-48, XT-60 and XT-70, and 18 x 40 inches for the XT-90. The 2023 Gemline brochure lists 15 x 15 x 41 for the 48 and 60 and 18 x 18 x 40 for the 70 and 90. Confirm the delivered size with the installer.
Sources and review scope
- NuGen Fusion XT installation instructions and owners manual, footer revision 5/10/2012; manufacturer-authored, hosted by distributor Consolidated Supply; retrieved October 8, 2026. Printed pages 4, 21, 24, 33 and 34.
- Gemline Water Softening Series brochure, PDF created May 2023; retrieved October 8, 2026. Pages 2 (performance data) and 3 (certified system specifications).
- Grains-per-pound figures and the sizing illustration are our arithmetic from the manufacturer’s rated capacities. They are not manufacturer claims.