4000/5000 GPD Whole House RO Filter Pack

Choose your replacement pack

Prefilter pack: the cartridge set only, without an RO membrane.

• Complete replacement pack, 4000 GPD: the 3 prefilters plus 2 x 4" x 40" RO membranes (CQE-RC-04086).
• Complete replacement pack, 5000 GPD: the 3 prefilters plus 3 x 4" x 40" RO membranes (CQE-RC-04086).

Check the size printed on your current membrane before ordering.

Complete replacement packs are one-time purchases. Replace prefilters typically every 12 to 24 months, about 18 months for most homes; once a year on chlorinated city water. Replace RO membranes every 2 to 3 years. Actual life depends on feed water quality, system configuration and usage.

A 4,000 or 5,000 GPD reverse osmosis system supplies a large home or a business, and it runs on two or three 4" x 40" membranes. Every gallon reaches them through three pre-filter stages. Keep those stages fresh and the membranes, pump and output stay where they should be.

The Prefilter pack holds the three pre-filter cartridges for a 4,000 or 5,000 GPD Crystal Quest whole house RO system: a pleated cellulose sediment cartridge, a SMART cartridge and a coconut-based carbon block cartridge, each 4-5/8" x 20" for 5" x 20" Big Blue housings.

At a glance

• The full pre-filter set: sediment (CQE-RC-04034), SMART (CQE-RC-04030) and carbon block (CQE-RC-04036)
• Big Blue 20" cartridges rated at 6 gpm for the SMART and carbon block stages at this size
• Membrane protection: particles down to 5 microns, plus chlorine and chloramine reduction ahead of the 4" x 40" elements
• Typical replacement 12 to 24 months, about 18 months for most homes, and once a year on chlorinated city water
• Prefilter pack: membranes not included

Inside the pack

The cartridges install in this order, inlet first. Sediment: pleated cellulose media on a polypropylene core, with vinyl plastisol end caps, rated at 5 microns; the pleats give it a large dirt-holding surface. SMART: Crystal Quest's multi-media cartridge with coconut shell carbon, catalytic carbon, redox alloy, ion-exchange resin, ceramic and tourmaline media. Carbon block: solid acid-washed coconut shell activated carbon, rated at 5 microns. These are the same part numbers Crystal Quest lists for these system sizes.

How the stages work together

Load the dirt early

The sediment stage takes the particle load, so the SMART and carbon media spend their capacity on chemistry instead of dirt, and the pump and membranes never see sand, silt or rust.

Two kinds of carbon for two disinfectants

Many cities disinfect with chloramine rather than chlorine. The SMART stage's catalytic carbon targets chloramine, which standard carbon handles less effectively; its coconut carbon, redox alloy and ion-exchange media also work on organic chemicals and metals. The carbon block then gives the water a final, close-contact pass for any remaining chlorine, taste and odor.

Why it matters to the membranes

The thin-film composite membranes in these systems tolerate less than 1 ppm chlorine, and the damage chlorine does is permanent. At 4,000 or 5,000 GPD, two or three membranes are at stake, so one fresh set of pre-filters protects all of them at once.

What it reduces

Primary targets (the jobs that protect your RO membranes):

• Sediment and suspended particles down to 5 microns, such as sand, silt and rust
• Chlorine and chloramine; the thin-film composite membranes tolerate less than 1 ppm chlorine, and the damage chlorine does is permanent
• Chlorine taste and odor

Also reduced by the SMART and carbon media: volatile organic compounds and other organic chemicals, and a range of metals. Performance depends on the contaminant, incoming water quality, flow and cartridge condition.

Not designed to treat: dissolved salts and TDS, which the RO membranes remove, or hardness above 15 gpg and iron or manganese above 0.05 ppm, which need their own pretreatment ahead of a 4,000 to 7,000 GPD system.

Why Crystal Quest

• The exact three parts our replacement tables list for 4,000 and 5,000 GPD, in the right order.
• Our own SMART blend for chloramine as well as chlorine.
• Over 1,000,000 people served since 1994. Crystal Quest builds under ISO 9001 quality management, has made water filtration in the USA for over 30 years and offers lifetime support by phone, email or chat.

Where it fits

• 4,000 GPD Whole House Reverse Osmosis System: two 4" x 40" membranes, sold separately.
• 5,000 GPD Whole House Reverse Osmosis System: three 4" x 40" membranes, sold separately.
• Commercial Mid-Flow RO System, 4,000 and 5,000 GPD: lists the same three part numbers.
• Not the 7,000 GPD: that size has a fourth pre-filter housing; order from its own replacement list.

RO filter cartridges are not returnable under our refund policy, so compare part numbers with your current cartridges or call us first.

Common questions

Pack contents

Stage details

The pack's GPD label names the whole house RO systems it serves (4000 and 5000 GPD). It does not include an RO membrane. Service life is an estimate: actual life depends on feed water quality, system configuration and usage.