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Osmio 4.5 x 20 Inch Active Ceramics Filter

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£360.00

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Osmio 4.5 x 20 Inch Active Ceramics Filter

Long life replacement active ceramics cartridge for compatible 4.5 x 20 inch whole house water filter housings, including the Osmio PRO III XL system.

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Osmio 4.5 x 20 Inch Active Ceramics Filter replacement cartridge

Replacement Active Ceramics Filter for Whole House Systems

  • Compatible Cartridge:

    Designed for compatible standard 4.5 x 20 inch whole house filter housings.

  • PRO III XL Replacement:

    This is the active ceramics replacement filter used in the Osmio PRO III XL Whole House Water Filter System.

  • Long Filter Life:

    Rated for approximately 2 to 3 years or up to 300,000 litres depending on water quality and usage.

  • Whole House Use:

    Designed to support filtered water throughout the property when fitted within a suitable whole house system.
Need the full system? View the Osmio PRO III XL Whole House Water Filter System or browse Replacement Filters.

What Does the Active Ceramics Filter Do?

The Osmio Active Ceramics Filter is designed as the first stage filter within the Osmio PRO III XL system. It uses a blend of active ceramics to treat incoming water before it passes through the additional carbon block and GAC/KDF filter stages.

It is intended for whole house filtration, helping improve the quality of water supplied to taps, showers, bathrooms and appliances when installed correctly as part of a compatible system.

Osmio Active Ceramics whole house water filter cartridge
Osmio 4.5 x 20 inch ceramic filter replacement for whole house filter housing

Designed for Long Service Life and Low Maintenance

  • Up to 300,000 Litres:

    The cartridge is rated for up to 300,000 litres, depending on local water conditions and household usage.

  • Typical 2 to 3 Year Replacement Cycle:

    The active ceramics cartridge normally lasts much longer than standard carbon filters.

  • No Backwashing Required:

    The cartridge is replaced at the end of its service life rather than requiring routine backwashing.

  • Whole House Flow Rate:

    Suitable for systems designed around flow rates up to approximately 70 litres per minute.

Is This the Correct Filter for Your System?

  • Correct For:

    Osmio PRO III XL Whole House Water Filter System active ceramics housing.

  • Also Suitable For:

    Compatible standard 4.5 x 20 inch blue or clear whole house filter housings.

  • Not Suitable For:

    Small under sink systems, countertop systems, reverse osmosis systems or non standard housings.

  • Check Before Ordering:

    Confirm your housing size and filter type before purchasing. If unsure, contact Regal Flow first.

Complete Your Filter Replacement

The Osmio PRO III XL uses three replacement cartridges, each with a different purpose and replacement interval.

Active Ceramics Filter

Long life filtration stage. Typically replaced every 2 to 3 years.

Current product

KDF and GAC Filter

Supports chlorine, taste and odour reduction while helping protect downstream filtration media. Typically replaced every 12 to 18 months.

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Carbon Block 5 Micron

Fine filtration and activated carbon polishing. Typically replaced every 6 to 12 months.

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Replacement Schedule Advice

Each cartridge works differently, so they should not automatically be replaced at the same time. Replacing the correct filter at the correct interval helps maintain system performance and avoids unnecessary cost.

Replace the Correct Stage, Not the Whole System

This cartridge replaces the Active Ceramics stage in a compatible 4.5 x 20 inch whole house filter housing. If you own the Osmio PRO III XL system, this is one of the three main filter stages and should be replaced on its own schedule rather than replacing every cartridge at the same time unnecessarily.

The Active Ceramics cartridge is the long life filter within the Osmio PRO III XL arrangement. The other cartridges in the system have different replacement intervals, so checking which cartridge needs replacing before ordering is important.

As a practical rule, this cartridge is usually replaced far less often than the carbon block filter. If your water quality, flow rate or taste has changed, it may also be worth checking the condition of the other filters in the system.

Compatible With the Osmio PRO III XL Whole House System

The Osmio PRO III XL system uses three separate filter stages. The Active Ceramics cartridge is fitted in the first housing and is designed for long life filtration across the whole home.

View the full Osmio PRO III XL Whole House Water Filter System if you need to confirm the complete setup.
Replacement active ceramics filter for Osmio PRO III XL system
Osmio ceramic filter replacement cartridge close up

Replacement Guidance

  • Turn Off the Water Supply:

    Always isolate the water supply before opening the filter housing.

  • Release Pressure First:

    Depressurise the housing before removing the sump to avoid leaks or sudden water release.

  • Check the O Ring:

    Inspect the housing seal before refitting to reduce the risk of leaks.

  • Flush After Replacement:

    Run water through the system after fitting the new cartridge, following your system guidance.

What Comes With This Product?

  • 1 x Osmio Active Ceramics Filter:

    4.5 x 20 inch replacement cartridge.

  • Filter Housing Not Included:

    This is a replacement cartridge only, not a complete whole house filter system.

  • Compatible System Sold Separately:

    The Osmio PRO III XL system is available separately from Regal Flow.

Important Compatibility Note

This product is a replacement cartridge, not a standalone water filter system. It must be installed inside a compatible 4.5 x 20 inch whole house filter housing. If you are unsure whether it fits your current setup, contact Regal Flow before ordering.

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View Replacement Filters

Osmio 4.5 x 20 Inch Active Ceramics Filter Specifications

Product Type Whole house replacement filter cartridge
Brand Osmio
Filter Type Active Ceramics
Size 4.5 x 20 inch
Compatible System Osmio PRO III XL Whole House Water Filter System
Compatible Housing Suitable standard 4.5 x 20 inch whole house filter housings
Typical Replacement Interval 2 to 3 years
Rated Capacity Up to 300,000 litres
Recommended Flow Rate Up to approximately 70 litres per minute
Maintenance Requirement Replace cartridge at end of service life
Housing Included No
Standalone System No, replacement cartridge only
Browse the Osmio Collection, shop Replacement Filters, or view the Osmio PRO III XL system.

Frequently Asked Questions

Is this a complete whole house water filter system?

No. This is a replacement cartridge only. It must be fitted inside a compatible 4.5 x 20 inch whole house filter housing.

Does this fit the Osmio PRO III XL?

Yes. This is the Active Ceramics replacement cartridge used in the Osmio PRO III XL Whole House Water Filter System.

How often should it be replaced?

The cartridge is typically replaced every 2 to 3 years or up to 300,000 litres, depending on usage and local water quality.

Does the housing come with it?

No. This product is the filter cartridge only. The filter housing or complete whole house system is sold separately.

Can I use it in any 4.5 x 20 inch housing?

It is suitable for compatible standard 4.5 x 20 inch whole house filter housings. Check your housing dimensions and setup before ordering.

Do I need a plumber to replace it?

Many customers use a qualified plumber, especially for whole house systems. The water supply must be isolated and pressure released before opening the housing.

Manufacturer Warranty

This Osmio replacement filter is supplied with the manufacturer's warranty against manufacturing defects, giving you added confidence when replacing your existing filter.

Need Help Confirming the Correct Osmio Filter?

If you are not sure whether this is the right replacement cartridge for your system, contact Regal Flow before ordering. We can help you check the model, housing size and replacement schedule.

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Replacement Filter Support

Unsure which Osmio cartridge needs replacing? Our support team is available 7 days a week to help you choose the correct filter before you order.

Contact Support Team
Email Support: info@regalflow.co.uk
Telephone Direct: 0121 630 1130

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