Pool Filter Source
Cartridge catalogULTRA-S5

Replacement cartridge

ULTRA-S5

Pleatco Ultra

A source-reviewed replacement used with 2 compatible filters. Confirm the equipment model and physical details before ordering.

Application
Spa filters
Compatible filters
2
Specifications
Dimensions reviewed
Last reviewed
July 26, 2026

Cartridge measurements

Size & end caps

How to measure
Outside diameter
5 in
Cap-to-cap length
13 5/16 in
Top
Open2 1/8 in opening
Bottom
Open2 1/8 in opening

Compatibility

Compatible pool and spa filters

Check the complete equipment label before choosing a cartridge.
Spa filterPentair Dynamic Series I–IV RDC-25 / RDC-25S1 cartridge neededSpa filterPentair Dynamic Series I–IV RDC-50 / RDC-50S1 cartridge needed

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