Coconut Based 5-Micron Carbon Block Filter Cartridge

That swimming-pool smell when you fill a glass. Coffee that tastes a little off. A chemical note in the shower. On chlorinated city water, that is usually chlorine, and activated carbon is the classic fix.

This replacement carbon block water filter is one solid block of acid-washed coconut shell activated carbon, rated at 5 microns. It reduces chlorine taste and odor, volatile organic compounds (VOCs) and fine sediment, so the water from your countertop, under-sink, reverse osmosis or whole house system tastes clean again. Four sizes fit standard 2.5 x 10, 2.5 x 20, 5 x 10 and 5 x 20 inch housings, including Crystal Quest systems.

At a glance

• Better-tasting water: reduces chlorine taste and odor and VOCs, the targets printed on every cartridge label
• Two jobs in one stage: carbon adsorption plus mechanical filtration of particles down to 5 microns
• Acid-washed coconut shell carbon formed into a solid block with a low pressure drop, so flow stays strong
• Four sizes, 0.5 to 6 GPM, for countertop, under-sink, RO and whole house housings
• Long service life: typically 12 to 24 months, about 18 months for most homes

What you are looking at

The photos show the cartridge as it ships: a dark carbon block inside a polyolefin wrap and polypropylene netting, closed with polypropylene end caps and a Buna-N gasket on top that seals against the housing cap. The label carries the part numbers, the pressure range and the replacement steps, so the next change is easy.

How a carbon block filter works

Adsorption on a huge internal surface

Activated carbon is carbon that has been treated with steam at very high temperature until it is full of tiny pores. That internal surface is enormous. As water passes through, many organic chemicals and the compounds behind chlorine taste and odor are attracted to the carbon and held on its surface. Chemists call this adsorption.

Why coconut shell, and why acid-washed

Crystal Quest specifies coconut shell carbon for this block and has it acid-washed, an extra processing step used to enhance how well activated carbon removes contaminants. The result is a clean, dense carbon made for drinking water.

Why a solid block

Loose granular carbon (GAC) adsorbs, but it does not strain. Because this carbon is one solid block, it does both: it adsorbs chemicals and it catches particles down to its 5-micron rating. You get carbon treatment and fine sediment filtration in a single housing.

Contact time matters

The longer water stays in contact with carbon, the more the carbon can adsorb. Each size carries its own rated flow, from 0.5 GPM for the 2-7/8" x 9-3/4" to 6 GPM for the 4-5/8" x 20". Taste and odor compounds take relatively little carbon to handle, which is a big reason a carbon block keeps water tasting clean for many months.

What it reduces

Primary targets (printed on the cartridge label):

• Chlorine taste and odor
• Volatile organic compounds (VOCs)
• Sediment and fine particles down to 5 microns

Also reduced by activated carbon, where present (a capability of the media, not a separate tested rating for this cartridge):

• Some pesticides and herbicides, such as atrazine
• Some disinfection byproducts, such as trihalomethanes (THMs)
• Other organic taste and odor compounds

Chloramine: activated carbon can reduce it, but a standard carbon block is less effective on chloramine than catalytic carbon. If your city uses chloramine, pair this block with a SMART Filter Cartridge, whose blend includes catalytic carbon.

Not designed to treat: bacteria and viruses, hardness minerals, fluoride, nitrate, total dissolved solids, or lead and other heavy metals. For those, Crystal Quest has dedicated stages such as the Lead Filter Cartridge, SMART cartridges and reverse osmosis.

Why Crystal Quest

• Specified for our own systems. This is the carbon block stage in Crystal Quest double and triple cartridge systems, Thunder under-sink RO systems and whole house RO pre-filtration, so a replacement matches what your system was designed around.
• Sized by real measurements. Every option is listed by actual cartridge diameter and length, not a loose nominal size.
• Over 1,000,000 people served since 1994. Crystal Quest builds under ISO 9001 quality management and has made water filtration in the USA for over 30 years.
• Lifetime support. Call, email or chat with our water filtration team whenever you have a question.

Where it fits

• Double cartridge systems: first stage, ahead of SMART
• Triple cartridge systems: last stage, after sediment and SMART
• Specialty triple systems: first stage, ahead of SMART and the specialty cartridge
• Thunder under-sink RO: third pre-filter, after UF and SMART, protecting the membrane
• Whole house RO with three pre-filter housings: after sediment and SMART
• Metal Removal triple cartridge systems: last stage, after the iron cartridge and SMART

Pick the size printed on your current cartridge or in your order history: 2-7/8" x 9-3/4" (CQE-RC-04000), 2-7/8" x 20" (CQE-RC-04014), 4-5/8" x 9-3/4" (CQE-RC-04035) or 4-5/8" x 20" (CQE-RC-04036).

Common questions