FreshWater ACE Cell Cleaner

• 1 × 12 fl oz bottle of FreshWater ACE Cell Cleaner — pre-measured cleaning solution in a bottle sized to hold the ACE cell during soaking
• Cell cleaning instructions — printed on the bottle label

• Pre-measured single-use solution — no mixing, no measuring, no estimation
• Bottle doubles as the cleaning vessel — drop the ACE cell directly into the bottle to soak
• Removes calcium scale from titanium electrodes — restoring full chlorine-generation efficiency
• Improves cell efficiency — a scaled cell works harder to produce the same chlorine output, which depletes it faster
• Maximizes ACE cell life — regular cleaning is the single biggest factor in how many years the cell will operate
• Quick 10-minute soak — the cell is back in the spa fast
• Specifically formulated for the ACE system — generic descalers can damage cell components; this product is purpose-built
• Genuine Watkins Wellness — designed by the same company that engineered the ACE cell

The ACE Cell Cleaner is a mild acidic solution that dissolves calcium carbonate scale — the white, crusty deposit that forms when calcium ions in your spa water combine with carbonate ions and precipitate onto the titanium electrodes of the ACE cell. Scale forms most aggressively on heated, electrified surfaces, which is exactly what an active salt cell looks like to dissolved calcium.

Here's what happens during a soak:

• The acidic solution contacts the scaled electrodes when the cell is submerged
• Calcium carbonate dissolves chemically back into calcium and carbonate ions in solution
• The deposit lifts off the electrode surfaces — visible as the solution becomes cloudy during the soak
• Titanium electrodes are exposed — fully clean and ready to generate chlorine at peak efficiency again

Why this matters in practical terms: a scaled cell has reduced electrode surface area available for the electrolysis reaction that creates chlorine. The ACE system compensates by running the cell harder — which works in the short term but accelerates electrode wear, raises operating costs, and ultimately shortens the cell's working life. Cleaning every three months keeps the cell working efficiently at lower output settings, which is how Watkins designed the system to operate.

Pro Tip: The single biggest factor controlling how often you need to clean the ACE cell is your spa water's calcium hardness. Keep calcium below 50 ppm using FreshWater Vanishing Act Calcium Remover, and you may only need to clean the cell every 3 months as recommended. Let calcium drift above 100 ppm, and you may end up cleaning monthly to keep up with scale formation. Cleaning addresses the symptom; managing calcium prevents the problem.

When to Clean the ACE Cell

• Every 3 months minimum as preventive maintenance — recommended by Watkins regardless of visible scale
• Anytime scale is visible when you look through the holes at the bottom of the ACE cell
• Monthly if your spa has hard fill water (calcium above 100 ppm)
• If the spa controller indicates a salt system issue despite a confirmed proper salt level
• If chlorine generation seems weaker than usual at the same Output setting

Cleaning Procedure

1. Power off the hot tub at the breaker in the electrical subpanel. Critical: the ACE cell must never be removed from water or placed into Cell Cleaner with power on.
2. Remove the ACE cell from the spa following your owner manual's instructions. Most ACE cells release from the spa interior with a twist.
3. Open the Cell Cleaner bottle.
4. Place the ACE cell directly into the bottle — the bottle is sized to hold the cell without overflow.
5. Let soak for approximately 10 minutes. You may see the solution cloud as scale dissolves off the electrodes; this is the product working.
6. Remove the cell from the cleaning solution after the soak.
7. Rinse the cell thoroughly under clean running water until no cleaning solution residue remains.
8. Reinstall the cell in the spa following your owner manual's instructions.
9. Restore power at the breaker.
10. Verify operation — within 24 hours, test the spa water and confirm normal chlorine generation has resumed (target: 3 ppm free chlorine residual at your usual Output setting).
11. Dispose of the empty cleaner bottle in household trash. The bottle is single-use.

Maximizing Cell Life Between Cleanings

• Keep calcium hardness at or below 50 ppm — use Vanishing Act Calcium Remover at fresh fills and as needed
• Maintain alkalinity 80–120 ppm and pH 7.2–7.8 — out-of-range water accelerates scale formation
• Run the lowest Output setting that maintains the chlorine residual you need
• Use FreshWater Stain & Scale Defense weekly as additional protection against mineral deposits
• Don't skip the every-3-month cleaning — even when scale isn't visible, electrode buildup happens at a microscopic level

Safety Notes

• Power MUST be off before removing the cell or placing it in the cleaning solution — this is a hard safety requirement, not a suggestion
• Avoid skin and eye contact with the cleaning solution — it's mildly acidic; rinse with water if exposure occurs
• Single-use bottle — do not refill or reuse after cleaning; the solution is depleted after one use
• Keep away from children and pets
• Do not mix with other chemicals
• Dispose of used solution per local regulations — diluted acidic solutions typically drain-safe, but check local guidance

Pro Tip: If your ACE cell has gone many months or years without cleaning and shows heavy scale, the first cleaning may not fully restore it. After the initial 10-minute soak, inspect the electrode surfaces — if you still see visible scale, a second bottle and a longer soak (up to 20 minutes) may be needed for a deep restoration. Going forward, regular every-3-month cleanings will prevent reaching this point again.

• Brand: FreshWater® (Watkins Wellness)
• Volume: 12 fl oz
• Form: Pre-measured single-use liquid descaling solution
• Function: Removes calcium carbonate scale from the Hot Spring ACE Salt Water System cell electrodes
• Bottle Design: Sized to hold the ACE cell directly during soaking
• Soak Time: Approximately 10 minutes (heavy scale may require up to 20 minutes)
• Recommended Cleaning Frequency: Every 3 months minimum; monthly in hard-water regions
• Compatible With: Hot Spring Highlife, Highlife NXT, and Limelight Collection spas equipped with the ACE Salt Water System (2004–2021 model years)
• Compatible Cell Part: Watkins ACE cell, part 76078
• NOT Compatible With: FreshWater Salt System cartridges (these are disposable, not cleanable), Caldera spas, Freeflow spas, non-Hot Spring salt systems, pool salt cells
• Use Frequency: Single-use bottle; one bottle = one cell cleaning
• Storage: Cool, dry location; sealed bottle; protect from freezing
• Shelf Life Sealed: 2+ years at room temperature
• Hazmat Classification: Non-hazmat — eligible for mail return per standard policy
• Country of Origin: Manufactured for Watkins Wellness, USA

FreshWater ACE Cell Cleaner is designed exclusively for the Hot Spring ACE Salt Water System cell. The ACE system was an option on specific Hot Spring spa models from 2004 through 2021.

Compatible With

• Hot Spring® Highlife® Collection — ACE-equipped models, 2004–2021
• Hot Spring® Highlife® NXT Collection — ACE-equipped models
• Hot Spring® Limelight® Collection — ACE-equipped models, 2004–2021
• The ACE replacement cell (Watkins part 76078) for the spa models above

NOT For

• FreshWater Salt System cartridges — these are disposable cartridges (part #80004) replaced every 4 months, not cleaned. Used in current Hot Spring Highlife/Limelight and Caldera Utopia/Paradise spas.
• Caldera spas of any series — Caldera uses the FreshWater Salt System, not ACE
• Hot Spring Hot Spot®, TX, SX, or Freeflow® spas — these are not salt-system-equipped
• Pool salt cells from any manufacturer — different design, different scale chemistry; this product isn't formulated for pool cells
• Other manufacturers' spa salt cells (Sundance, Jacuzzi, Bullfrog, etc.) — proprietary fitment and different chemistry; use their manufacturer-specific cleaner
• General descaling tasks in the spa — this product is formulated for the cell, not for spa shells, jets, or heaters

Works Alongside

• FreshWater Vanishing Act Calcium Remover — essential pair; keeping calcium below 50 ppm dramatically reduces how often you need to clean the cell
• FreshWater Salt Test Strips — verify proper salt level (~1,750 ppm) after cell cleaning and any maintenance
• FreshWater 5-Way Test Strips — confirm overall water balance before and after cleaning
• FreshWater Spa Salt — the salt the cell converts to chlorine
• FreshWater Stain & Scale Defense — weekly sequestrant prevents calcium and metals from depositing on the cell between cleanings

Pro Tip: ACE-equipped Hot Spring spas are an installed base — these models were sold from 2004 to 2021, but they're still in service. If your spa is in this range and you're not actively maintaining the ACE cell with periodic cleanings, the cell is probably running scaled and is wearing out faster than necessary. Three months between cleanings is the manufacturer-recommended baseline; you may need more frequent cleanings if you have hard fill water.