For a farm, small business or very large home that needs certified Class A treatment at high flow. Most homes are better served by the PRO20 or smaller.
Amazon $5,030
The certified pick for a large home or a small business on a private well. It costs a lot, but the dose is measured and certified.
- 20 GPM at 40 mJ/cm²Flow
- Class ANSF/ANSI 55
- MercuryLamp
- 5 yearsWarranty
Price checked November 2, 2026. As an Amazon Associate we earn from qualifying purchases.
- Certified by NSF to NSF/ANSI 55 Class A at a full 20 GPM, enough for a large home
- UV sensor plus flow meter show the real dose, and a plug in valve can stop water if it drops
- Amalgam lamp lasts about two years between changes
- 5 year controller and 10 year chamber warranty
- Priced for professional installs, several times a budget 24 GPM unit
- Must be mounted vertically, and the 31 in chamber needs clearance above it for lamp changes
- The shutoff valve is sold separately
The Viqua PRO family
Every Viqua PRO model we rank, smallest first. Ratings compare each against its own flow.
| Model | Flow | Rating | Price |
|---|---|---|---|
| Viqua PRO10 | 10 GPM at 40 mJ/cm² | 3.4/5 | $3,174.98 |
| Viqua PRO20 (this one) | 20 GPM at 40 mJ/cm² | 3.6/5 | $3,840 |
| Viqua PRO30 | 30 GPM at 40 mJ/cm² | 3.6/5 | $5,030 |
How it scores
The rating comes from 5 measured or published factors, each scored 0-100 against fixed reference points for its flow. How we rank explains each one.
Specifications
| Model number | 650653 |
|---|---|
| Disinfection | |
| Rated flow | 20 GPM at 40 mJ/cm² |
| NSF/ANSI 55 | Class A |
| Lamp | Mercury |
| Lamp power | 140 W |
| Lamp life | 18,000 hours |
| Monitoring | |
| UV intensity sensor | Yes |
| Lamp failure alarm | Yes |
| Lamp change countdown | Yes |
| Shutoff valve | Yes |
| Build | |
| Chamber | 316L stainless steel |
| Ports | 1.2 in |
| Maximum pressure | 125 psi |
| Voltage | 120 V |
| Warranty | 5 years |
Alternatives in this flow
The monitored version of Viqua’s large home unit, for well owners who want to know the dose is actually being delivered. Worth the premium over the plain VH410 if no one checks the water regularly.
Amazon $1,310A large home unit with a published Class A dose flow and a 3 year controller warranty, for less than Viqua’s monitored models. Add a sensor if no one tests the water.
Amazon $1,069.14Compare
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