How to Remove Calcium Buildup From Hot Tub

Calcium buildup, also called scale, forms when the water has high levels of calcium and the pH balance is off. When water is too hard, calcium sticks to the hot tub shell, jets, and pipes. Over time, this can clog jets, damage pumps, and leave white flakes in your water.

Signs of Calcium Buildup

• White, chalky spots on hot tub surfaces

• Cloudy water or floating white flakes

• Reduced water flow from jets

• Hard, crusty residue around water lines

Tools and Products You'll Need

Before starting, gather the right tools and supplies:

• Hot tub surface cleaner or white vinegar

• Non-abrasive scrubbing pads or brushes

• Descaling agent or hot tub cleaner designed for calcium

• Water test strips or digital water tester

• Spa vacuum (optional for large flakes)

Step-by-Step Guide to Removing Calcium Buildup

Follow these steps to clean your hot tub and get rid of calcium deposits:

1. Drain the Hot Tub

Start by turning off the power and draining the hot tub completely. This gives you full access to the surfaces and jets.

2. Scrub Visible Deposits

Use a soft scrubbing pad and a spa-safe cleaner to scrub away white spots or hard buildup. White vinegar can also help loosen scale.

• Avoid using steel wool or harsh brushes

• Focus on areas near jets and water lines

3. Clean the Jets

Calcium often clogs the jets. Remove any detachable jets and soak them in a vinegar-water mix for 30 minutes. Scrub gently and rinse before reinstalling.

4. Refill and Add Descaler

Refill the tub with clean water. Add a descaling product according to the instructions. This will help flush calcium from inside the pipes.

5. Run the Jets

Turn the power back on and run the jets for at least 30 minutes. This helps circulate the descaler and break down buildup in hidden areas.

6. Drain and Rinse Again

After circulating the cleaner, drain the hot tub one more time. Rinse all surfaces and refill with fresh water.

How to Prevent Future Buildup

Removing calcium is only part of the solution. Proper water care helps stop scale from forming again.

Keep Water Balanced

Use test strips to check your water at least twice a week. Keep these levels in the proper range:

• Calcium hardness: 150 to 250 ppm

• pH level: 7.2 to 7.6

• Total alkalinity: 80 to 120 ppm

Use a Water Softener or Pre-Filter

If you live in an area with hard water, consider using a hose pre-filter when filling your spa. This reduces the amount of calcium in the water.

Shock and Sanitize Regularly

Keeping your water sanitized helps prevent all types of residue, including calcium. Shock your spa weekly or after heavy use.

Clean the Filters Monthly

Dirty filters make it harder to balance your water. Rinse your filters weekly and deep clean them with a filter cleaner once a month.

When to Call a Professional

If calcium buildup is severe or keeps coming back despite your efforts, it may be time to contact a hot tub technician. A pro can inspect your spa’s plumbing and suggest upgrades like a water softening system or more advanced filtration.

Your Hot Tub Deserves Better Than Buildup

With a few simple steps and the right habits, you can keep your hot tub free from calcium and running like new. Staying ahead of the buildup means clearer water, better jet performance, and a more enjoyable soak every time you use your spa.