The short answer
A portable softener is sized in gallons, not people: grain rating ÷ hardness in gpg = gallons between regenerations. A 16,000-grain unit treats about 1,600 gallons of 10 gpg water or 800 of 20 gpg. Regenerate by pouring table salt into the tank and flushing with fresh water, following the maker's amount.
Gallons between regenerations
| Rating | 10 gpg | 15 gpg | 20 gpg |
|---|---|---|---|
| 8,000 | 800 | 530 | 400 |
| 10,000 | 1,000 | 670 | 500 |
| 16,000 | 1,600 | 1,070 | 800 |
Units we cover
On The Go OTG4-DBLSOFT 16,000 and PRO+AQUA 16,000 are typical; see the full shortlist.
On the road
- Test campground water with strips; hardness varies a lot by site.
- Regenerate before storage and run fresh water until the salt taste is gone.
- Check the hose fittings and the unit's stated flow against your RV's demand.
Products mentioned
Questions readers ask
How often do I regenerate an RV water softener?
When the gallons since the last regeneration reach the rating divided by your hardness, or when test strips show hardness coming through.
What salt do I use?
Plain table or softener salt as the maker directs; follow its amount per regeneration.