--- title: "Iron Filters for Well Water: Air Injection vs Manganese Greensand (2026)" description: "Orange staining, metallic taste, and rotten-egg smell almost always point to iron and sulfur. Here is how to pick the right whole-house iron filter for your well." lang: en json-ld: | [ { "@context": "https://schema.org", "@type": "Organization", "name": "Whole House Water Treatment", "url": "https://wholehousewatertreatment.com", "description": "Independent U.S. reviews of whole-house water filters, softeners and reverse osmosis systems, plus state and city water-quality guides." }, { "@context": "https://schema.org", "@type": "Article", "headline": "Iron Filters for Well Water: Air Injection vs Manganese Greensand", "description": "Orange staining, metallic taste, and rotten-egg smell almost always point to iron and sulfur. Here is how to pick the right whole-house iron filter for your well.", "datePublished": "2026-01", "dateModified": "2026-01", "author": { "@type": "Organization", "name": "Whole House Water Treatment", "url": "https://wholehousewatertreatment.com" }, "publisher": { "@type": "Organization", "name": "Whole House Water Treatment", "logo": { "@type": "ImageObject", "url": "https://wholehousewatertreatment.com/favicon.png" } }, "mainEntityOfPage": { "@type": "WebPage", "@id": "https://wholehousewatertreatment.com/buying-guides/iron-filters-for-well-water" }, "image": "https://wholehousewatertreatment.com/__l5e/assets-v1/77d9e822-fe0d-4a62-a3e8-fad5ffbb0cea/og-default.png" }, { "@context": "https://schema.org", "@type": "BreadcrumbList", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "Home", "item": "https://wholehousewatertreatment.com/" }, { "@type": "ListItem", "position": 2, "name": "Buying guides", "item": "https://wholehousewatertreatment.com/buying-guides" }, { "@type": "ListItem", "position": 3, "name": "Iron Filters for Well Water: Air Injection vs Manganese Greensand", "item": "https://wholehousewatertreatment.com/buying-guides/iron-filters-for-well-water" } ] } ] --- [![Whole House Water Treatment logo](/assets/logo-Cd_iTZFZ.png)Whole House Water Treatment WHWT ](/) [Find Your System](/find-your-system)[Best Filters](/best-whole-house-water-filters)[Best Softeners](/best-water-softeners)[Well Water](/best-well-water-filtration-systems)[Water Quality](/water-quality)[Guides](/buying-guides)[Learn](/learn)[About](/about) 1. [Home](/) 2. [Buying guides](/buying-guides) 3. Iron Filters for Well Water: Air Injection vs Manganese Greensand Buying guide · 7 min read # Iron Filters for Well Water: Air Injection vs Manganese Greensand ![Private water well head and pump in a grassy rural yard](/assets/hero-well-water-CtPLRe-t.jpg) Iron and hydrogen sulfide are the two most common well-water complaints in North America. Both are technically aesthetic (not regulated by the EPA at the levels most homeowners see), but both will ruin laundry, appliances, and shower fixtures within a year if left untreated. The good news: a single whole-house iron filter handles both, as long as you size it to your actual water test. ## Test first, buy second Before you shop, get a certified lab panel that reports total iron, ferrous vs ferric iron, manganese, hydrogen sulfide (H2S), pH, and dissolved oxygen. Each of those numbers picks the technology. Air-injection filters work well when total iron is under about 8 ppm, manganese is under 2 ppm, and H2S is moderate. Above those thresholds, or with very low pH, you need a different system or pre-treatment (often a small chemical feed pump). ## Air injection: the default for most wells An air-injection iron filter draws an air pocket into the top of the tank during each cycle. The dissolved iron (ferrous, invisible) hits the air, oxidizes to ferric (rust-colored particles), and the media bed traps it. The next backwash flushes everything to drain. This is the dominant whole-house iron technology today because it does not need chemicals, and one tank handles iron, manganese, and most H2S. SpringWell, Aquasana, and SoftPro all sell well-water variants of this design. Sizing matters more than brand. Match the tank size to your peak flow (count fixtures) and the iron load in ppm. Undersized tanks short-cycle and let iron break through. ## Manganese greensand: the heavy-duty alternative Greensand uses a coated media that needs to be regenerated with potassium permanganate (a chemical feed pump and a small tank of solution). It handles much higher iron and manganese loads than air injection, and works at lower pH. The trade-off is maintenance: you are now responsible for keeping a chemical tank topped up and disposing of spent permanganate. Most homeowners with moderate iron prefer the simplicity of air injection. ## What to install upstream and downstream Upstream: a 100-micron spin-down sediment pre-filter protects the iron tank from grit. If you have very low pH (below 6.8), add a calcite neutralizer before the iron filter, because iron oxidation needs neutral water. Downstream: install your softener AFTER the iron filter. Softener resin is destroyed by ferric iron, and the iron filter is what produces ferric iron. If you skip the iron filter and rely on the softener alone, the resin will fail within 1 to 2 years. If your test also flags bacteria, finish the stack with a UV disinfection unit (covered in its own guide). The order at the point of entry is: sediment, iron filter, softener, UV. ## Recommended products that solve this Here are the systems that match this guide. We do not show prices because manufacturers change them often, the buttons open the brand's current pricing in a new tab. Top pick SpringWell ### SpringWell WS Well Water Filter Well water (air injection) [![SpringWell WS standalone air-injection well water iron filter](https://www.springwellwater.com/wp-content/uploads/2025/03/WS1.png)](https://www.springwellwater.com/product/well-water/whole-house-iron-filter/) Image: [SpringWell product page →](https://www.springwellwater.com/product/well-water/whole-house-iron-filter/) Air-injection iron filter that handles iron up to 7 ppm, sulfur and manganese in one tank, our top well-water pick. [Check latest price on SpringWell](https://www.springwellwater.com/product/well-water/whole-house-iron-filter/)[Read full review →](/reviews/springwell-well-water) Also consider Aquasana ### Aquasana Rhino Well Water Well water filter Alternative well-water system from Aquasana, bundles iron oxidation with a salt-based softener stage. [Check latest price on Aquasana](https://www.aquasana.com/whole-house-water-filters/well-water-filter-systems.html)[Read full review →](/reviews/aquasana-rhino-well) ## Keep reading - [City water vs well water →](/buying-guides/city-water-vs-well-water) - [UV purifiers for well water →](/buying-guides/uv-purifiers-for-well-water) ## More buying guides - [ City Water vs Well Water: Which Whole House System Do You Need? 7 min read ](/buying-guides/city-water-vs-well-water) - [ Salt-Based vs Salt-Free Softeners: The Honest Comparison 6 min read ](/buying-guides/salt-based-vs-salt-free-softeners) - [ Sizing a Whole House Water Filter: Flow, Fixtures, and Tank Size 5 min read ](/buying-guides/sizing-a-whole-house-water-filter) - [ UV Purifiers for Well Water: When You Need One and What to Buy 6 min read ](/buying-guides/uv-purifiers-for-well-water) - [ Water Testing: Home Kits vs Certified Labs (And When Each Makes Sense) 6 min read ](/buying-guides/water-testing-at-home-vs-certified-lab) Whole House Water Treatment Independent, U.S.-focused reviews and water-quality guides for whole-house filters, softeners and reverse osmosis systems. Informational only - not medical or safety advice. Reviews - [Find Your System (tool)](/find-your-system) - [Best whole house filters](/best-whole-house-water-filters) - [Best water softeners](/best-water-softeners) - [Best well water systems](/best-well-water-filtration-systems) - [Water quality by state](/water-quality) - [Buying guides](/buying-guides) Site - [About](/about) - [Affiliate disclosure](/affiliate-disclosure) - [Privacy policy](/privacy-policy) - [Terms](/terms) © 2026 Whole House Water Treatment. As an independent marketing partner of SpringWell, Aquasana, SoftPro and Pelican, we may earn commissions from qualifying purchases. Prices, specifications and certifications are subject to change - always verify on the manufacturer's site before purchasing.