Nelsen Water Solutions AIO & Filter Systems

Air-injection (AIO) iron & sulfur filters

Nelsen AIO systems use a pocket of compressed air inside the tank to oxidize dissolved iron, manganese and hydrogen-sulfide gas so they can be filtered out and flushed away during regeneration — no chemicals, no separate feed pump. They're the simplest whole-house fix for orange staining and the classic rotten-egg smell on well water.

How to choose the right AIO size

• Test first: match the system to your measured iron (ppm), manganese, and hydrogen sulfide levels, plus your peak flow rate (bathrooms + appliances running at once).
• Iron up to ~10 ppm and moderate sulfur are well within range for a single AIO tank; very high iron or pH below 6.8 may need pretreatment.
• Flow: a 10" x 54" tank suits most 1–3 bath homes; size up for larger homes or higher demand.

AIO vs. chemical injection

AIO is lower-maintenance than chlorine or peroxide injection because there's nothing to refill — the air draw and backwash are automatic. For extreme iron/sulfur or bacterial iron, a chemical feed system or our UV setup may be the better route.

Common questions

Will it remove the smell completely? Properly sized to your sulfur level, yes — AIO is specifically designed for hydrogen-sulfide odor.

Does it waste water? Only during a brief periodic backwash, similar to a softener.

Ships across the U.S. — free shipping on orders over $1,000; smaller and international orders are quoted by carrier and weight at checkout.

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