The Omnipure K5555 is a 10" x 2.5" inline deionization filter that uses mixed bed resin to remove dissolved ions from water, producing ultra-pure deionized water for sensitive applications. With dual 1/4" FQC and 1/4" FPT fittings on both ends, this inline DI filter integrates seamlessly into RO systems, aquariums, labs, and anywhere low TDS water is required.
SPECIFICATIONS
Omnipure K5555 Technical Details
| Model Number | K5555 (also K5555-JJ, K5555-BB) |
| Dimensions | 10" L x 2.5" W |
| Filtration Media | Mixed Bed DI Resin |
| Capacity | 230 Grains of Hardness |
| Flow Rate | 0.5 GPM |
| Fitting Connections | 1/4" FQC and 1/4" FPT on both ends |
| Maximum Pressure | 125 PSIG |
| Maximum Temperature | 100°F |
INSTALLATION & USE
How to Install the K5555 Inline DI Filter
- Turn off water supply and depressurize your system before installation.
- Connect the inlet side of the K5555 to your water source using the 1/4" quick connect or 1/4" FPT fitting. The filter can be oriented in any direction.
- Connect the outlet side to your destination line using the appropriate fitting type for your setup.
- Turn water back on slowly and check for leaks at both connection points.
- Flush the filter for 2-3 minutes before first use. Replace the filter when TDS levels begin to rise or capacity is exhausted.
COMPATIBILITY
Where the K5555 Works Best
The Omnipure K5555 inline DI filter is designed for post-RO polishing in reverse osmosis systems, aquarium water preparation, hydroponics, laboratory applications, and any system requiring deionized water with extremely low TDS. The dual fitting options (1/4" quick connect and 1/4" FPT) make it compatible with most standard inline water filter configurations. Note that 1/4" NPT fittings measure approximately 0.540" on a ruler, not 0.25", which is a common source of confusion when matching threads.
🔧 Pro Tip: Monitor your outlet TDS regularly with a meter. Mixed bed DI resin exhausts suddenly rather than gradually, so tracking TDS trends helps you replace the K5555 before water quality drops off completely.
