The VH410 kills bacteria, including coliform and E. coli, as the water flows past the lamp. VIQUA says its UV systems are capable of inactivating common waterborne pathogens, including Cryptosporidium (chlorine-resistant), Giardia, pathogenic E. coli, hepatitis A, norovirus, Legionella, Salmonella, and Campylobacter, with efficacy demonstrated in its internal testing. It achieves this through UV-C light at 254 nanometers, which scrambles microbial DNA on contact. VIQUA rates the VH410 at 18 GPM at its standard 30 mJ/cm² dose and 14 GPM at 40 mJ/cm².

Aidan puts the VH410 in almost every well home, whether there are two people or ten: with bacteria, he says, it is never overkill. It delivers 18 GPM of UV-treated water at VIQUA's standard dose (14 at 40 mJ/cm2), which covers simultaneous showers, kitchen use, laundry, and outdoor faucets. The Viqua VH200 (9 GPM, $895) is the shorter unit for a tight space. The VH410 costs only $100 more and gives you double the flow.

Every 12 months, regardless of whether the bulb still appears to be working. UV-C output degrades over time even though the bulb continues to glow. By month 12, output may drop to 60–70% of original intensity, not enough for full disinfection. The VH410's electronic controller tracks lamp life and alerts you when replacement is due. The replacement lamp (S410RL-HO) costs $170 and the swap takes about 15 minutes.

Yes. VIQUA requires a 5-micron sediment filter upstream of the UV chamber. It catches particulates that could shadow bacteria from the UV light. If your water has iron above 0.3 ppm, hardness above 7 grains per gallon, or any visible cloudiness, you need to address those issues before adding UV. Iron fouls the quartz sleeve within weeks, and turbidity creates shadows where bacteria survive. Clean water first, then UV as the final disinfection step.

We recommend installation by a licensed plumber; Aidan supports your plumber by phone at 800-460-5810. A licensed plumber typically needs about an hour for the UV alone. The unit mounts to the wall and splices into the main water line. You need shutoff valves on both sides, a standard 120V GFCI outlet, and copper fittings at the UV chamber connections (PEX does not work well at these connection points). Leave 24 inches of clearance below for maintenance access.

The VH200 delivers 9 GPM of UV-treated water and is the shorter unit for a tight space ($895). The VH410 delivers 18 GPM, double the capacity, and is the one Aidan recommends for most well homes ($995). VIQUA rates both at the same doses: 9 and 18 GPM at its standard 30 mJ/cm² dose, 7 and 14 GPM at 40 mJ/cm². Both use the same electronic controller technology. The VH410 uses 1-inch connections versus the VH200's ¾-inch, and costs only $100 more. For a detailed comparison, see our Viqua VH200 vs VH410 guide.

No. UV is a disinfection technology -- it kills living organisms but does not physically remove anything from the water. It has no effect on iron, manganese, sediment, chemicals, heavy metals, hardness, or taste and odor. If your water has these issues in addition to bacteria, you need separate treatment for each problem. The typical treatment sequence is: sediment filter → acid neutralizer (if pH is low) → iron filter → water softener (if needed) → UV system.