At Isopure Water, we work hard to make sure you understand the science behind your water filtration system. One of the more advanced—and incredibly effective—methods we use is anion exchange. But what does anion exchange remove, and why should you care?

Let’s walk you through what it is, what it removes, and when it’s the right solution for your home or business.

What Is Anion Exchange and How Does It Work?


Anion exchange is a filtration process that uses a special resin to swap negatively charged ions (anions) in your water with harmless ones like chloride or hydroxide. These resins are typically made from beads coated in functional groups that attract and capture specific contaminants.

This type of treatment is commonly found in industrial water treatment, commercial operations, and even residential systems that need high purity water—especially for applications like drinking, rinsing, or food preparation.

What Anion Exchange Removes from Your Water

Now to the big question: what exactly does anion exchange remove?

Here’s a breakdown of the key contaminants and substances:
  • Nitrates – Common in agricultural runoff and fertilizers; dangerous in high levels.
  • Sulfates – Cause scaling and bitter taste in drinking water.
  • Chromates and Arsenic – Toxic heavy metals that pose serious health risks.
  • Fluoride – Can be removed if levels are above recommended limits.
  • Tannins – Naturally occurring organics that cause yellowish water and unpleasant taste.
  • Silica – A tough ion to remove that can damage RO membranes or interfere with equipment.
At Isopure Water, we often recommend anion exchange systems when water tests show elevated levels of these substances.

When to Use Anion Exchange Systems

Anion exchange systems aren’t always required for basic water softening, but they’re crucial when you need high-purity water or when you're dealing with specific contaminants like nitrates or arsenic.

We often pair anion exchange resins with other treatment types, including reverse osmosis or carbon filtration, to ensure complete purification.

Recommended Anion Exchange Products We Carry

If you're looking to upgrade your filtration setup, we stock some of the best resin options available. These are great for replacing media in your existing systems or building a custom solution:

Purolite A-850 Tannin Selective Gel Acrylic Resin
Perfect for tannin and organic matter removal—especially from well water.

Purolite FerrIX-A33 ArsenX NP Resin
Specially formulated to remove arsenic efficiently using a hybrid anion exchange design.

Purolite UXMB-1XSC Mixed Bed Resin
Used for final polishing in ultrapure water applications—great for labs, electronics, and more.

Need Help Choosing the Right Resin?

We know choosing the right system or replacement media can feel overwhelming. That’s why our experts are always here to help. If your latest water test revealed high levels of nitrates, fluoride, arsenic, or tannins, anion exchange might be the solution you’ve been looking for.

Use our live chat, give us a call, or contact us here—we’ll match you with the exact media or system you need.

Shop Anion Exchange Resins at Isopure Water

Whether you're replacing a cartridge or planning a complete system overhaul, we carry top-quality anion exchange resins for a wide range of needs.

Explore our Resin & Media Collection and get fast shipping and support from real water treatment experts.