Arsenic Removal Inline / Reverse Osmosis Filter Cartridge

Arsenic has no taste, no color and no smell, so a water test is the only way to know it is there. It occurs naturally in rock and soil, which is why it turns up most often in well water, and in some regions far more than others.

If your test shows arsenic, this inline cartridge, part CQE-RC-04062, adds a dedicated arsenic-reduction stage right where you drink: before or after a point-of-use RO membrane, on an ice maker or refrigerator line, or inside a water cooler or fountain. Its label says it simply: removes and reduces arsenic.

At a glance

• A dedicated arsenic stage for point-of-use systems, separate from your carbon and sediment stages
• Arsenic-selective media that captures arsenic as water flows through
• Fits where you need it: pre or post RO, refrigerator and ice maker lines, water coolers and fountains
• Inline and sealed: plumbed on the water line with threaded connectors, replaced as one piece
• Made in the USA, as printed on the cartridge label

What you are looking at

A white, sealed inline cartridge with an elbow connector at each end. The label reads "Crystal Quest Arsenic Reduction Inline Cartridge" and shows the flow arrow, part number, operating limits and nine numbered replacement steps. The media is sealed inside, so a change is a clean swap of the whole cartridge.

How arsenic reduction works

Two forms of arsenic

Arsenic in drinking water comes in two main forms. Arsenate, the oxidized form, carries a negative charge at normal drinking water pH. Arsenite, the reduced form common in oxygen-poor groundwater, carries almost no charge. That difference decides how well any arsenic media can catch it.

Capture on selective media

Arsenic-selective media is built with sites that hold arsenate strongly as water flows past. Because arsenate is charged, it is drawn to those sites and held, while the water continues on. Uncharged arsenite has little to hold on to, so it passes far more easily.

Why oxidation and water chemistry matter

Chlorine converts arsenite to arsenate. On chlorinated city water, most arsenic already arrives in the form the media captures best. On well water without chlorination, some arsenic may be arsenite, and an oxidation step ahead of the media makes treatment far more effective. Other dissolved ions in your water also compete for the same sites, so how long the media lasts depends on your full water chemistry, not just the arsenic number on your report.

What it reduces

Primary target (printed on the cartridge label): arsenic.

Not designed to treat: chlorine and chemical tastes, fluoride, nitrate, dissolved solids, or bacteria and viruses. Those are handled by other stages, such as a SMART inline cartridge and the RO membrane. Use it only on water that is microbiologically safe.

Is it right for my water? Start with a test. An Arsenic Test confirms whether arsenic is present and gives you a baseline to check the treated water against. If your water is from a well and is not chlorinated, or your arsenic is high, talk to a Crystal Quest specialist first: the form of arsenic and the rest of your water chemistry decide the right treatment, and a whole-house or multi-stage approach may fit better than a single point-of-use stage.

Why Crystal Quest

• A dedicated stage, not an afterthought. Arsenic gets its own cartridge and media instead of sharing space in a general-purpose filter.
• Made for our systems. Crystal Quest lists this cartridge as the optional arsenic stage for its under-sink RO, countertop RO and water cooler systems.
• Straight answers about your water. We tell you what this cartridge is built for, what affects its life and when to call us before buying.
• 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

• Thunder under-sink RO systems: listed as the optional arsenic cartridge, CQE-RC-04062, on Thunder system pages such as the Thunder 1000C.
• The Countertop Reverse Osmosis System: listed as its optional arsenic stage.
• Bottleless water coolers: the optional Water Cooler/Reverse Osmosis Arsenic cartridge in the water cooler manual.
• Refrigerator and ice maker lines: plumbed inline on the supply tubing. It is not a slot-in replacement for a refrigerator's built-in filter.

There is no single fixed position for optional inline stages in every system. Its published applications include both pre and post point-of-use RO; install it where your system's manual specifies. Need arsenic treatment in a standard drop-in housing instead? See the Arsenic Removal Filter Cartridge.

Common questions