How to Start Up and Maintain a Softub with Softcare

Softubs aren’t like rigid-shell spas: the vinyl liner, the barrel motor, and the warranty all have opinions about your water chemistry. Softcare® is Softub’s own chlorine-based product line, formulated to be safe on the liner, and Softub’s Water Treatment Guide is very specific about what does — and doesn’t — go in the water. This guide follows it step by step.

Softub warranty warning: Per Softub’s official Water Treatment Guide, using potassium monopersulfate (MPS / “non-chlorine”) shock voids the Softub warranty. Superchlorinate with Softcare Granular Dichlor or FROG® Jump Start® instead. FROG @ease® products used per FROG’s guidelines are the documented exception and do not void the warranty.

Who the Softcare System Is Best For

Every Softub owner, honestly — Softcare is the manufacturer’s own line, matched to the vinyl liner and the 3–5 ppm chlorine program Softub specifies. If you’d rather run a lower steady chlorine level with less hands-on dosing, the FROG @ease Floating System is the one floating dispenser Softub has tested and approved for Softubs — our @ease guide covers it. Everything below is the classic Softcare chlorine routine.

Products and Supplies You’ll Need

Softcare Chlorine (Granular Dichlor) — the sanitizer.
Softcare 4-in-1 Test Strips — chlorine, pH, alkalinity, hardness.
Softcare pH Up and Softcare pH Down.
Softcare Calcium Increaser.
Softcare Metal Gone — for metals in source water.
Softcare Water Clear clarifier and Water Quality Enhancer.
Softcare Defoam — for foam flare-ups.
Softcare Instant Filter Cleaner and a spare OEM Softub filter.
Softcare Jet Line Cleaner — plumbing purge at drain time.
Softub Cleaner & Conditioner — for the liner at water changes.

Softcare by Softub chlorinating granules 2 pound bottle for Softub spas

Softcare Chlorine (Granular Dichlor)

Softcare by Softub 4-in-1 test strips for chlorine, pH, alkalinity and hardness

Softcare 4-in-1 Test Strips

Step 1: Prep and Fill

Rinse the filter or install a clean one (dirty filters are the #1 cause of cloudy Softub water).
Confirm the drain cap is snug and the pump connections look right.
Fill with fresh water — a hose pre-filter reduces sediment and metals on the way in.
On well water or any staining history, add Softcare Metal Gone after filling.
Let the motor heat the water; Softub recommends adding chlorine once the water is above 80°F.

Step 2: Balance Your Water

Balance in this order: Total Alkalinity → pH → Calcium Hardness

Softub’s recommended water balance

Total Alkalinity: 80–120 ppm

pH: 7.2–7.8 (ideal 7.5)

Calcium Hardness: 150–250 ppm

Free Chlorine: 3–5 ppm

Source: Softub Water Treatment Guide. Balance alkalinity first, then pH, then hardness — within the first 24 hours of filling. pH discipline matters more in a Softub than any other spa: low pH wrinkles the vinyl liner and corrodes the motor (and can void the warranty); high pH scales the liner and plumbing.

Softub chemical rules (from the official guide): add only one chemical at a time, with the lid completely off and the water circulating for at least 15 minutes after each addition. Test before adding anything — readings aren’t accurate for several hours after chemicals go in. And hot tubs vary in size and water capacity: always follow the dosage instructions on the product bottle for your Softub’s gallon capacity.

Step 3: Start Up the Chlorine

With the pump running and water above 80°F, add Softcare Chlorine per the label: 1/2 teaspoon per 100 gallons as an initial treatment, repeated at 15–20 minute intervals until a 3–5 ppm free chlorine residual is established on your test strips. Your Softub’s gallon capacity depends on the model (Sportster, Legend, Resort, Portico, PoseidonX) — check your owner’s materials and dose from actual gallons.

Softub sizes its doses in teaspoons for a reason: these are small water volumes, and over-chlorinating over time damages the liner. Measure — don’t pour from the jar.

Step 4: Testing & Weekly Routine

Test after each use — at least twice a week

That’s Softub’s published minimum, and they mean it: neglected chemistry damages the liner, and the guide states improper water maintenance can void the warranty. Keep free chlorine at 3–5 ppm, pH near 7.5, alkalinity 80–120.

The weekly rhythm

Test; dose Softcare Chlorine per label to hold 3–5 ppm.
Superchlorinate per the label (1 teaspoon per 100 gallons) after heavy use — as often as nightly in a busy tub, or weekly in a moderately used one. Never MPS shock (warranty).
Rinse the filter; monthly, soak it in Instant Filter Cleaner. A second filter lets you swap and dry-rotate.
A capful of Water Quality Enhancer per its label keeps water feel and clarity up between changes.
Wipe the waterline scum ring gently with a soft pad and baking soda (Softub’s own recommendation — no abrasives or household cleaners on the liner).

Troubleshooting (Straight from Softub’s Guide)

Symptom	Likely cause	Fix
Cloudy water	Organics, low sanitizer, balance off, dirty filter	Adjust chlorine; rebalance; clean filter with Instant Filter Cleaner
Cloudy green	Low sanitizer	Test and re-establish 3–5 ppm chlorine
Brown water / odor	Dissolved iron, copper, or manganese	Metal Gone; check pH
Chalky white scale	High calcium	Check balance and adjust
Eye/skin irritation	Chloramines or balance off	Superchlorinate with dichlor; adjust pH/alkalinity
Waterline scum	Body oils, lotions, detergents	Soft pad + baking soda
Excessive foaming	Oils, cosmetics, detergents	Defoam + dichlor as needed — see our foaming guide

When to Drain and Refill

Softub recommends emptying, cleaning, and refilling 3–4 times per year, or sooner when chemistry becomes hard to manage. At each change: run Jet Line Cleaner through the plumbing before draining, clean the liner with Softub Cleaner & Conditioner, then refill and rebalance from the top of this guide.

Never use in a Softub (per the official guide): MPS/non-chlorine shock, floating tablet dispensers (they bleach the liner — FROG @ease is the tested exception), gas chlorination, ionizers, salts, scents, bath bombs, or soaps not approved for Softubs. Never place chlorine granules or bromine tablets in any dispenser or directly on the liner, and never mix chemicals with each other.

Softub Softcare FAQs

Softub’s Water Treatment Guide specifies 3-5 ppm free available chlorine, with pH 7.2-7.8 (ideal 7.5), alkalinity 80-120 ppm, and calcium hardness 150-250 ppm. Test with Softcare 4-in-1 strips after each use and at least twice a week.

The label dose is 1/2 teaspoon per 100 gallons as an initial treatment, repeated at 15-20 minute intervals until you read 3-5 ppm, and 1 teaspoon per 100 gallons for superchlorination. Softub models vary in capacity, so calculate from your model’s actual gallons and follow the bottle label.

No. Softub’s official Water Treatment Guide states that potassium monopersulfate shock voids the warranty. To superchlorinate, use Softcare Granular Dichlor or FROG Jump Start. FROG @ease products used per FROG’s guidelines are the documented exception to the floating-dispenser and shock rules.

No – floating dispensers can park against the vinyl and bleach the liner by over-concentration, and Softub’s guide prohibits them. The single tested-and-approved exception is the FROG @ease Floating System used according to FROG’s instructions.

Because of the vinyl liner: sustained low pH causes wrinkles in the liner and corrosion in the motor, and Softub warns it can void the warranty. High pH scales the liner and plumbing instead. Keep pH 7.2-7.8, ideally 7.5, and fix alkalinity first so pH stays put.

Softub recommends a full empty, clean, and refill 3-4 times per year – or sooner whenever chemistry becomes difficult. Run Jet Line Cleaner before draining and clean the liner with Cleaner & Conditioner while it’s empty.

Add chlorine once the water is above 80°F. Balance alkalinity and pH within the first 24 hours of filling, handle hardness and any metals, then start the chlorine as the tub comes up to temperature.

Need help? You’re never on your own.

We stock the full Softcare line and Softub filters, covers, and accessories — and for model-specific technical questions, Softub’s own support team is excellent.

Softub Technical Support

1-800-711-5382, ext. 2 — for water treatment and equipment questions.

EZ Hot Tub Parts

Every Softcare product on this page ships from our shelves — and we answer Softub parts questions daily.

Related EZ Water Care Guides

FROG @ease Floating System Guide

The one floating system Softub has approved for Softubs — steady low-level chlorine with mineral assist, and less day-to-day dosing.

Why Is My Hot Tub Foaming?

Foam hits soft-sided tubs too. What actually causes it, how to knock it down today, and how to keep it from coming back.

Browse all guides on the EZ Hot Tub Water Care hub.