Softub Water Care & Maintenance
A Softub is not a pool. It’s not a standard acrylic hot tub. The water care is different — and getting it right protects both your warranty and your liner.
Softub specifies Softcare products for a reason. Using the wrong chemicals can damage your vinyl liner and may void your warranty. The Softcare line is formulated specifically for Softub’s flexible vinyl construction — it is not interchangeable with generic hot tub chemicals.
The previous authorized Minnesota dealer — MinneSoftub in Mound — made this a priority with every customer they sold. We do the same.
Drain and Refill Every 2–3 Months
Everything that goes into your Softub stays there. Body oils, sweat, lotions, sunscreen, detergent from swimwear, chemical byproducts — it all builds up into what’s called Total Dissolved Solids (TDS). Your filter can’t remove it. Your sanitizer can’t destroy it. It just accumulates until the water stops responding properly.
For a Softub specifically, old contaminated water releases gases and chemical byproducts that attack the vinyl liner over time. You won’t see the damage happening — but you’ll see the result eventually. Premature liner aging, loss of flexibility, surface dulling, and cracking are the direct result of water left in too long. Not bad luck. Not a manufacturing defect. Old water.
Three months is the limit — not the goal
With normal use, aim for every 2 months. Three months is the absolute maximum. Heavy use means every 6–8 weeks. Your liner and your chemistry will both thank you.
And yes — even if you haven’t been using the tub. An unused Softub still needs draining on schedule. The water is still aging. Sanitizer is still reacting with whatever is dissolved in it. Airborne contaminants still enter. The tub sits quietly going chemically stale whether anyone is soaking in it or not.
Normal vs. Heavy Bather Load
The more people using the tub and the more frequently, the faster dissolved waste builds up. Adjust your drain schedule accordingly.
- 1–2 people
- 2–4 times per week
- 15–30 minute soaks
- 3 or more people
- Daily or multiple sessions
- Frequent guests
Flush the Jet Lines First
Before every drain and refill, run Softcare Jet Line Cleaner through the system. Biofilm — a bacterial film — builds up inside the plumbing lines over time. You can’t see it, but it’s there. Draining without flushing first leaves that biofilm in the lines to contaminate your fresh water immediately.
Add the Jet Line Cleaner to your warm water with the jets running, let it circulate, then drain. It’s a small investment that protects everything that comes after it.
Softcare Jet Line Cleaner —How to Drain, Clean, and Refill Your Softub
-
1Add Jet Line Cleaner and run jets
With water at temperature, remove the filter, add Jet Line Cleaner, run jets for 20 minutes with air on. Then drain.
Softcare Jet Line Cleaner — -
2Drain completely
Drain all water from the tub. Don’t leave standing water in the bottom.
-
3Wipe down the liner
Use Softcare Cleaner and Conditioner on the vinyl liner. Do not use household cleaners, bleach, Magic Erasers, or abrasive pads — they damage the vinyl’s protective surface. Rinse thoroughly.
Softcare Cleaner & Conditioner — -
4Clean or replace the filter
Use Softcare Instant Filter Cleaner or replace the filter if it’s due. A clean filter going into fresh water performs correctly from day one.
Softcare Instant Filter Cleaner — -
5Refill with fresh water
If you’re on well water or have older plumbing, add Softcare Metal Gone at fill to address iron, manganese, and copper before they cause staining or scaling.
Softcare Metal Gone — -
6Balance the water — in the correct order
Balance at bathing temperature. Order matters — each adjustment affects the next. See the balancing order below.
-
7Add sanitizer and you’re done
Add Softcare Chlorine or start your Frog @Ease system. Test with Softcare 4-in-1 test strips to confirm everything is in range before your first soak.
Softcare Chlorine — Test Strips 4-in-1 —
Balance in the Correct Order
Every adjustment you make to your water affects what comes next. Getting the order wrong means chasing your tail. Do it in this sequence every time, at bathing temperature.
Calcium Hardness matters especially for Softubs. Low calcium makes vinyl more absorbent — it picks up oils, metals, and contaminants faster, leading to tide lines, staining, and premature liner aging. Keep CH at a minimum of 100–150 ppm.
Softcare Calcium Increaser — Softcare pH Down — Softcare pH Up —Frog @Ease — Softub Uses It Themselves
Factory verified.
When we toured the Softub factory, all five models on the floor were being maintained with Frog @Ease. That’s not a marketing claim — that’s what we saw. Frog @Ease is a Softub-approved water care system that uses SmartChlor technology and mineral sanitization to keep water balanced with less hands-on management. It’s a legitimate alternative to the traditional Softcare chlorine routine for owners who want a simpler weekly system.
Which Softub Filter Do You Need?
Softub changed their drain cover from 4″ to 5″ in 2009 to comply with federal VGB drain cover regulations. The filters are not interchangeable. Here’s how to identify which one you need without guessing.
5″ drain cover — snap ring matches filter size
The snap ring is the same diameter as the filter cartridge and sits centered. If they match, you have a post-2009 Softub — order the 5″ filter.
4″ drain cover — snap ring is smaller and off-center
The snap ring is noticeably smaller than the filter cartridge and sits off-center. If the snap ring doesn’t match the filter diameter, you have a pre-2009 Softub — order the 4″ filter.
The DuraSock filter sock acts as a pre-filter, catching coarse debris — sand, grit, hair — before it embeds in the filter pleats. Rinse it weekly and use it every time. Softub filters aren’t cheap — the sock protects your investment.
Softcare by Softub — Complete Water Care
Everything you need to maintain your Softub correctly is available on EZhottubparts.com. Every product in the Softcare line is formulated specifically for Softub’s vinyl construction and approved for use under the Softub warranty.
Questions About Your Softub Water?
Call or text our service department. We’ll give you a straight answer.