Viqua PRO20
#2 in Over 12 GPMFull review
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.
Amazon $3,840$3,840
The Viqua PRO20 is the better UV water purifier overall, rated 3.6 to 2.7. The Viqua PRO20 leads on certification, monitoring and warranty. The Viqua VP600 costs $2,610 less ($1,230 vs $3,840).
Viqua VP600
#5 in Over 12 GPMFull review
A plain high flow Viqua for large homes that don’t need a sensor, at well under the price of the certified PRO units. Add the VP600M if you want monitoring.
Amazon $1,230$1,230
Prices were last checked November 2, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Which should you buy?
- Choose the Viqua PRO20 for certification (NSF/ANSI 55 Class A vs not NSF/ANSI 55 certified; flow rated at a stated 40 mJ/cm² dose), monitoring (UV intensity sensor, lamp failure alarm, shutoff valve, lamp change countdown vs lamp failure alarm, lamp change countdown) and warranty (5-year warranty vs 3-year warranty).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every over 12 GPM UV water purifier; a clear win is highlighted. How we rank explains each one.
| Factor weight | Viqua PRO20 | Viqua VP600 |
|---|---|---|
| Overall rating | 3.6/5 | 2.7/5 |
| Value 25% | 16 $192 per GPM ($3,840, 20 GPM at 40 mJ/cm²) | 55 $68.33 per GPM ($1,230, 18 GPM at 40 mJ/cm²) |
| Certification 20% | 100 NSF/ANSI 55 Class A | 30 not NSF/ANSI 55 certified; flow rated at a stated 40 mJ/cm² dose |
| Monitoring 20% | 100 UV intensity sensor, lamp failure alarm, shutoff valve, lamp change countdown | 40 lamp failure alarm, lamp change countdown |
| Lamp life 10% | 44 18,000 hour mercury lamp | 6 9,000 hour mercury lamp |
| Warranty 25% | 44 5-year warranty | 22 3-year warranty |
Specifications
| Viqua PRO20 | Viqua VP600 | |
|---|---|---|
| Disinfection | ||
| Rated flow | 20 GPM at 40 mJ/cm² | 18 GPM at 40 mJ/cm² |
| NSF/ANSI 55 | Class A | No |
| Lamp | Mercury | Mercury |
| Lamp power | 140 W | 58 W |
| Lamp life | 18,000 hours | 9,000 hours |
| Monitoring | ||
| UV intensity sensor | Yes | No |
| Lamp failure alarm | Yes | Yes |
| Lamp change countdown | Yes | Yes |
| Shutoff valve | Yes | No |
| Build | ||
| Chamber | 316L stainless steel | 304 stainless steel |
| Ports | 1.2 in | 1 in |
| Maximum pressure | 125 psi | 125 psi |
| Voltage | 120 V | 120 V |
| Warranty | 5 years | 3 years |