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Frizzlife PX600 RO Reverse Osmosis System (8-Stage, 600GPD)
Frizzlife PD1000-TAM4 (1000 GPD, Tankless, Alkaline)
Frizzlife PD400 Tankless Reverse Osmosis System (400 GPD)
Frizzlife PX500-A Reverse Osmosis System (Alkaline, 500 GPD)
Frizzlife WB99-H Countertop Reverse Osmosis Filter (Silver, With Heating Function)
Frizzlife Reverse Osmosis Water Filter
Frizzlife makes under-sink and countertop water filters, and its reverse osmosis line is split into three families. Model numbers tell you most of what you need: the number is the daily output in US gallons per day (GPD), and a TAM suffix means an alkaline remineralisation filter is fitted.
The PD400, PD1000-TAM4 and PD1200 are slim tankless reverse osmosis systems with twist-in cartridges and a dedicated drinking water faucet. Frizzlife also sells the 600 GPD tankless reverse osmosis PD600-TAM3 and the 800 GPD tankless PD800-TAM4 in this family; both share the ASR211 first-stage cartridge with the PD400.
The PX500-A and PX600 are 8-stage tankless RO units with a 2:1 pure-to-drain ratio and a smart LED panel that shows TDS and a filter life reminder with colour indicators.
The WB99-H sits on the worktop like a large kettle and pours into a 1.4 litre pitcher you can keep in the fridge. You fill it from the tap, so there is no drilling or plumbing, which makes it the obvious pick for renters.
Figures below come from the Amazon UK listings for the systems in this collection. GPD is a maximum under test conditions; the flow rate is what you notice at the tap.
| Model | Type | Daily output | Flow | Stages | Pure : drain | Max feed TDS | Filter changes |
|---|---|---|---|---|---|---|---|
| PD400 | Tankless under sink | 400 GPD (about 1,514 L) | 0.28 GPM | 2 cartridges | 1.5 : 1 | 1,000 ppm | Pre filter 12 months, membrane 24 months |
| PX500-A | Tankless, alkaline | 500 GPD (about 1,893 L) | 0.4 GPM at 60 psi | 8 | 2 : 1 | 1,200 ppm | Pre 6 months, membrane 2 years, post 1 year |
| PX600 | Tankless under sink | 600 GPD (about 2,271 L) | 1.59 L/min | 8 | 2 : 1 | 500 ppm | Shown on the LED panel |
| PD1000-TAM4 | Tankless, alkaline | 1000 GPD (about 3,785 L) | 2.65 L/min | 9 | 2 : 1 | 600 ppm | Pre 1 year, membrane 2 years, TAM4 1 year |
| PD1200 | Tankless, smart faucet | 1200 GPD (about 4,542 L) | Fastest in the range | 11 | 3 : 1 | 1,000 ppm | Pre 12 months, membrane 24 months |
| WB99-H | Countertop, hot water | 100 GPD | Batch from 4.5 L tank | RO + LED + alkaline | - | - | FCR 12 months, SC 90 days |
Every model follows the same pattern of reverse osmosis filtration: protect the membrane, let the membrane do the heavy lifting, then polish the taste.
A sediment and activated carbon filter cartridge (ASR211 on the PD400, PD600-TAM3 and PD800-TAM4) traps rust and grit and cuts chlorine. That stops chlorine damaging the membrane and is the part you change most often.
A pump pushes water through a 0.0001 micron RO membrane. It holds back most total dissolved solids, including the calcium that causes limescale in hard-water areas, plus many heavy metals such as lead and other impurities. The rejected water goes to the drain.
A carbon filter at the end polishes the taste. On TAM3, TAM4 and PX500-A models an alkaline stage adds some mineral content back and raises the pH above 7.5. Frizzlife says its TAM3 adds 10-30 ppm to the TDS reading, so a pen test after that stage will read higher than the display.
The result is reverse osmosis water with far fewer dissolved solids than your tap supply, which most people notice first in clearer ice, cleaner kettles and less scum on tea.
Traditional RO systems fill a pressurised storage tank slowly and serve from that, which takes up most of a cupboard. Every Frizzlife under-sink model is tankless: the pump filters on demand, so there is no tank to sanitise and you keep far more cabinet space. The trade-off is that tankless units need a plug socket under the sink. If you are weighing up the design, compare our tankless reverse osmosis systems with tank-fed 5-stage systems.
TDS (total dissolved solids, in ppm) is the simplest way to see your water quality change. Frizzlife builds the reading into the unit or the tap:
Fewer joints mean fewer places to drip. Frizzlife's tankless units use an integrated waterway with the filters loaded at the factory, so there are only a handful of push-fit connections to make. Even so, it is worth:
Any reverse osmosis system sends some water to the drain to flush away what the membrane rejects. The pure-to-drain ratio tells you how much:
For a household drinking and cooking with 10 litres a day, moving from 1.5:1 to 3:1 saves over a thousand litres a year, which matters on a water meter.
The PX600 or PX500-A gives 500-600 GPD, 8 stages and a 2:1 ratio. The PX500-A adds the alkaline stage if you find plain RO water tastes flat.
The PD1000-TAM4 fills a kettle quickly at 2.65 litres per minute, and the PD1200 adds the 3:1 ratio and a smart faucet with a real-time TDS display.
The PD400 is the simplest model with only two cartridges to change, and Frizzlife quotes around 30 minutes to fit it.
The WB99-H needs only a socket. It also heats water for tea, coffee and baby formula. If you want something you can carry between rooms, see our portable RO systems too.
Every model has quick-change cartridges that twist out in seconds with no tools, and the panel or faucet warns you when one is due. Budget for:
Leaving cartridges in too long matters. The Drinking Water Inspectorate warns that missing changes lets deposits build up and creates a breeding ground for bacteria.
Frizzlife lists NSF/ANSI standards on many models, and the water quality claims you can rely on are the certified ones. NSF/ANSI 42 covers taste and odour, NSF/ANSI 53 covers specific health-related contaminants, NSF/ANSI 58 is the reverse osmosis standard and NSF/ANSI 372 covers lead in parts that touch water. The PD1000-TAM4 lists all four; the WB99-H is certified to NSF/ANSI 58. Certification only covers the claims tested, so check each listing.
Treat "99.99%" marketing with care. Frizzlife's own FAQ says the PD1200 removes about 94-95% of TDS, which is typical for a good membrane. If your feed water is 300 ppm, expect something like 15-20 ppm out.
Frizzlife is a specialist water filter company with a UK website, an email support team, installation videos and stocked replacement cartridges, and its tankless units carry hundreds to thousands of Amazon UK ratings, mostly 4.2-4.5 stars. The main complaints in reviews are about fitting the faucet and early TDS readings, both covered in the FAQs below. Our 8-stage RO collection puts the PX models alongside rivals.
If you are shopping by brand, Frizzlife's strengths are its compact, space saving tankless design and quick-change filters. Most rival reverse osmosis systems use 5 to 8 stages too, so compare our 6-stage and 7-stage systems on drain ratio and flow rather than stage count alone. Waterdrop RO systems compete directly on smart tankless units, iSpring systems lean towards traditional tank setups with standard housings, AquaTru filters are countertop only, and APEC water systems stick with a classic tank and drinking water faucet.
The Drinking Water Inspectorate says tap water in England and Wales is among the best in the world, and that extra treatment is not needed to protect your health. A Frizzlife system is about taste, softer water for kettles and coffee machines, and cutting bottled water. Check your area's hardness and quality on the DWI consumer pages or with your water company before choosing a model, especially if your feed TDS is high.
The tankless under-sink models use a pump and plug into a socket. The WB99-H countertop also plugs in to filter and heat.
Frizzlife explains that the pump pressurises air into the water; the bubbles release when you pour and clear in seconds. It is normal in the first weeks.
When the system sits idle a few ions cross the membrane. Readings drop back to normal after running it for about a minute.
Yes, reverse osmosis reduces fluoride and the dissolved calcium that causes limescale, which is why kettles stay clean. Exact figures vary by model and feed water, and the PX500-A listing adds that it can feed a fridge ice maker with a connection kit.
For support, spare filters and warranty details, go through the Frizzlife UK website or the Amazon UK seller; cartridges are listed by model number, so note yours when you fit it.
