PTL20W-SV-P4 Softub Screw-On Spa Filter - 6" × 5½" Replacement Cartridge

Keep your Softub water clean and clear with a reusable screw-on spa filter cartridge featuring a 1.5-inch threaded connection.

The PTL20W-SV-P4 replacement spa filter is designed for compatible Softub hot tubs that use a screw-on filter connection.

Featuring a 6-inch diameter, 5½-inch height, convenient handle top, and 1.5-inch male pipe thread (MPT) bottom, this replacement cartridge provides a practical solution for maintaining proper spa filtration.

Its pleated filter media helps capture dirt, debris, and other particles as water circulates through your hot tub.

Key Features & Benefits

• Compatible Softub Replacement: Designed for applicable Softub models with a matching threaded filter connection.

• 6" Diameter x 5½" Height: Compact cartridge dimensions for identifying the correct replacement.

• 1.5" MPT Threaded Bottom: Male threaded connection for compatible screw-on filter fittings.

• Convenient Handle Top: Helps with cartridge removal and installation.

• Reusable Filter Media: Can be rinsed and cleaned during routine spa maintenance.

• Effective Water Filtration: Helps capture dirt, debris, and suspended particles.

• Easy Replacement: Screw-on design for compatible filtration systems.

• Available in Canada: Supplied by Splash Pool & Spa in Peterborough, Ontario.

Product Specifications

Softub Compatibility - Check Before Ordering

This filter is designed for compatible Softub models requiring a 1.5-inch MPT screw-on filter cartridge.

Not all Softub filters use the same attachment system. Before ordering, confirm:

• Your existing filter has a male threaded bottom.

• The thread specification is 1.5-inch MPT.

• The cartridge measures approximately 6 inches in diameter and 5½ inches in height.

• Your filter has the appropriate handle-top configuration.

Screw-On vs. Snap-On Softub Filters

Softub filter systems may use different connection styles.

Screw-On Filter: Uses a threaded connection that attaches to a compatible fitting.

Snap-On Filter: Uses a different attachment mechanism and should not be assumed interchangeable with threaded cartridges.

If you're unsure which filter your Softub requires, contact Splash Pool & Spa with a photo of your existing filter and connection.

How to Clean Your Softub Spa Filter

Regular cleaning helps maintain water circulation and filtration performance.

1. Disconnect your Softub from electrical power before removing the filter.

2. Unscrew the existing cartridge according to the spa manufacturer's instructions.

3. Rinse between the pleats with clean water to remove accumulated debris.

4. Use a spa filter cleaning solution when needed, following its label instructions.

5. Rinse thoroughly before reinstalling.

6. Carefully screw the cartridge back into its compatible fitting without overtightening.

Do not force the threads or use an incompatible fitting.

When Should You Replace Your Spa Filter?

Consider replacing your filter cartridge if:

• The pleats are damaged or deteriorating.

• The threaded connection is cracked or worn.

• The filter remains heavily soiled after cleaning.

• Water circulation remains restricted after proper cleaning.

• The cartridge no longer maintains satisfactory filtration performance.

Regular filter care, proper sanitizer levels, and routine water testing help keep your spa ready for use.

Frequently Asked Questions

Will this fit my Softub?

This cartridge is intended for compatible Softub models that use a 1.5-inch MPT screw-on filter connection. Confirm the dimensions and attachment style before ordering.

What are the filter dimensions?

The cartridge is listed as 6 inches in diameter and 5½ inches in height, with a handle top and 1.5-inch MPT threaded bottom.

Is this a snap-on Softub filter?

No. This is a screw-on filter cartridge with a male threaded connection.

Can I clean and reuse this cartridge?

Yes. The pleated filter media is designed for periodic cleaning and reuse until the cartridge becomes worn or damaged.

Is this a genuine Softub OEM filter?

This product is listed as a Softub-compatible replacement cartridge. OEM manufacturer status has not been confirmed.

How often should I clean the filter?

Inspect it regularly and clean according to your spa's maintenance instructions. More frequent cleaning may be necessary with heavier spa use.

Shop Softub-Compatible Spa Filters in Canada

Splash Pool & Spa in Peterborough, Ontario, supplies spa filters, water care products, genuine Softub replacement parts, and compatible maintenance accessories.

We can help you identify the correct filter connection and choose the right replacement cartridge for your spa.

Need help confirming the fit? Contact Splash Pool & Spa with a photo of your existing filter before ordering.