Filters Fast Logo Header
Free Shipping on orders over $99 | FREE 365-DAY RETURNS

Product Availability

Please provide your e-mail address below to receive a notification when this product becomes available:


Thanks! We'll send you a notification when this product is available!


Filbur FC-3965 Replacement For Caldera 100 Filter


Retail: $69.99 /ea
You Save: 14%
As low as
Retail: $69.99
You Save: 14%
Ships in 1 to 2 business days.
Home Filter Club

Sign up for the Home Filter Club in checkout. You choose how often you want your filter, and we take care of the rest. Home Filter Club
Purchasing for a Business?

Contact [email protected] to gain access to case quantity discounts, account management and terms! Home Business Services

The Filbur FC-3965 is a compatible replacement for the following pool and spa filters:

  • Caldera 100
  • Caldera Spas 1039607
  • Unicel C-8399
  • Pleatco PCD100W
  • Watkins 73722

The Filbur FC-3965 is a compatible replacement spa filter for the Caldera 100 spa filter. This compatible filter replacement will fit all spas, jacuzzis, and hot tubs which use the Caldera 100 Spa Filter.

Filbur FC-3965 Spa Filter Replacement Product Specifications:

  • 3 oz.
  • Length: 16 1/2"
  • Outer Diameter: 8"
  • Top: Handle
  • Bottom: 3 5/8" open hole
  • Square Feet: 100 square feet

This compatible Filbur FC-3965 spa filter is made of advanced Reemay spunbound polyester pleated filter media with thermally bonded polyurethane caps and punched PVC pipe cores which ensures durability and consistent flow.

In addition to replacing the Caldera 100 spa filter, this compatible Filbur spa filter replacement will fit many other spas including those made by American Products, Harmsco, Pac Fab, Pentair Pool Products, Premier, Purex, Rainbow Plastics, Springwater, Sta-Rite, Watkins, and other manufacturers - compare the dimensions of this filter to your old filter before purchasing in order to determine size compatibility.

Cleaning your Filbur Pool and Spa Filters

  • It is time to clean your spa or pool filter cartridge when you notice a decrease in the pressure from your jets, or when the pressure in your spa filter tank increases by 8 psi from when the filter was newly installed.
  • In order to clean the spa filter, first remove it from its canister and use a garden hose to dislodge any debris between the pleats. Soak the spa filter in commercially prepared filter cleaner, or spray with the same to remove organic material and oils. To remove stains soak overnight in a solution of one quart bleach and 5 gallons of water.
  • Thoroughly rinse the spa filter cartridge with fresh water and reinstall it into the canister. Be sure to follow manufacturer's directions for installing the replacement spa filter.
  • DO NOT use a high-pressure car wash wand, a stiff brush or acid wash to clean the spa filter cartridges as these methods can damage the filter media.

Compatible Parts:

The Filbur FC-3965 Replacement For Caldera 100 Filter is the correct replacement for the following part numbers:

  • Caldera 100
  • Caldera Spas 1039607
  • PCD100W
  • Pleatco PCD100W
  • Unicel C-8399