Product Overview

The Unicel C-7375 Replacement Filter Cartridge is a 75 sq. ft. spa filter cartridge designed for select Caldera Spas using the newer-style 75 sq. ft. cartridge. Built with high-quality polyester filter media, this cartridge helps capture dirt, oils, debris, and fine particles to keep spa water cleaner and clearer.

This replacement cartridge is commonly used as an OEM-style replacement for Caldera spa part numbers 1019301 and 73531. It features a semi-circular handle top and an open bottom with a 2-11/16 in. inside diameter.

Ideal For

Caldera Spas using new-style 75 sq. ft. cartridges
Replacing worn or dirty spa filters
Improving spa water clarity
Routine hot tub maintenance
Reducing debris in spa water
Spa service technicians
Residential spa owners

Key Features

75 sq. ft. replacement spa filter cartridge
Designed for select Caldera Spa models
Replaces Caldera part numbers 1019301 and 73531
Compatible cross-reference for Pleatco PCD75N and Filbur FC-3964
7 in. outside diameter
14-3/4 in. length
Semi-circular handle top
Open bottom with 2-11/16 in. inside diameter
216 pleats for strong filtration capacity
3 oz Reemay 2033 polyester filter media
Helps capture dirt, oils, debris, and fine particles
Drop-in replacement for compatible spa filter housings

Benefits

The Unicel C-7375 helps maintain clean and clear spa water by trapping debris and contaminants as water circulates through the filter system. Replacing an old or clogged filter cartridge can improve water flow, reduce strain on the spa pump, and make chemical maintenance easier.

Its 75 sq. ft. filtration area and 216-pleat design provide strong debris-holding capacity for compatible Caldera spa systems. The semi-circular handle makes cartridge removal easier during cleaning and replacement.

Specifications

Customer-Facing Q&A

What does the Unicel C-7375 fit?
The C-7375 fits select Caldera Spas that use the newer-style 75 sq. ft. filter cartridge, including replacements for Caldera part numbers 1019301 and 73531.

What are the dimensions?
This cartridge measures 7 in. outside diameter by 14-3/4 in. long, with a semi-circular handle top and a 2-11/16 in. open bottom.

Is this the same as Pleatco PCD75N?
Yes. The Unicel C-7375 is commonly cross-referenced with Pleatco PCD75N and Filbur FC-3964.

Is this for pools or spas?
This is a spa and hot tub filter cartridge, commonly used with compatible Caldera spa models.

How often should I replace this cartridge?
Replacement timing depends on spa usage, water care, and cleaning frequency. Replace the cartridge when it is damaged, heavily stained, clogged, has collapsed pleats, or no longer restores water flow after cleaning.

Can I order based only on the spa brand?
No. Always confirm the cartridge dimensions, bottom opening size, top style, and existing part number before ordering. Caldera has used different filter styles across different models and years.

Confirm Before Ordering

Confirm the following before purchasing:

Filter area: 75 sq. ft.
Outside diameter: 7 in.
Length: 14-3/4 in.
Top style: Semi-circular handle
Bottom style: Open
Bottom inside diameter: 2-11/16 in.
OEM cross-reference: Caldera 1019301 / 73531
Compatible cross-reference: Pleatco PCD75N / Filbur FC-3964

Do not order based on spa brand alone. Filter cartridge compatibility depends on exact dimensions, end cap style, bottom opening size, and OEM part number.