Product Price Filter Capacity (gallons) Flow Rate (GPM (Gallons Per Minute)) Contaminant Removal Installation Difficulty Warranty (years) Water Pressure Requirement (PSI (Pounds per Square Inch))
Clearly Filtered Clearly Filtered Under Sink 3-Stage Filtration System
US
£294.81 2000 gallons 1.08 GPM Targets up to 232+ contaminants Quick and easy DIY (about 10-15 min) Limited lifetime warranty (warranted for 24 months) Designed for standard residential water pressure (~60 psi)

Three-stage under-sink system using Affinity filtration to target hundreds of contaminants while preserving beneficial minerals. Suits households wanting high contaminant coverage without RO complexity or drain line and who prefer an easy DIY install.

Aquasana Aquasana OptimH2O Under Sink 2-Stage (Claryum)
US
£74.44 500 gallons 0.5 gpm Reduces 78 contaminants including lead PFAS microplastics chlorine cysts VOCs asbestos pharmaceuticals pesticides herbicides DIY installation; easy do-it-yourself (no plumber required) 1 Year Limited Warranty 20-80 psi

Two-stage Claryum under-sink filter uses selective filtration to remove a wide range of contaminants while retaining beneficial minerals. Suited for homeowners who want certified contaminant reduction with easy DIY installation and filter changes every 6 months.

Waterdrop WD-G3P600 (G3P600 8-Stage Reverse Osmosis System)
US
£292.77 CF 6 months or 550 gallons; CB 12 months or 1100 gallons; RO 24 months or 2200 gallons 600 GPD Reduces TDS, PFOA, PFOS, fluoride, arsenic, lead, chlorine, chromium-6 and 1000+ contaminants DIY install in about 30 minutes 1 year

The Waterdrop G3P600 is a tankless 8-stage under-sink RO system delivering fast 600 GPD production with a 2:1 pure-to-drain ratio and NSF certifications. It suits users wanting high-capacity, space-saving RO filtration with replaceable CF/CB/RO cartridges and optional remineralization.

APEC APEC ROES-50 Essence Series (ROES-50)
US
£171.97 50 GPD @ 60 psi Removes up to 99% of contaminants including chlorine, fluoride, arsenic, lead, chromium, heavy metals, bacteria, virus DIY with provided hardware; requires under-sink installation 2 year with registration 40-85 psi

The APEC ROES-50 is a 5-stage under-sink reverse osmosis system providing up to 50 gallons per day of purified water and a 4 gallon storage tank. It suits homeowners who want high contaminant removal and are comfortable with standard under-sink RO installation and maintenance.

Frizzlife Frizzlife MK99 (Under Sink 3-Stage Filter)
US
£44.66 up to 2 years (replace cartridge every 6-8 months recommended) 2 GPM @ 60 psi lead, chlorine, tastes, odour, particulates, cysts (performance data: cyst 99.95%) easy, tool-free, 3 minute setup with quick-change twist-in design One year limited warranty Min. 20 psi, Max. 80 psi

Compact under-sink 2-stage system with 0.5 micron filtration, high flow and auto shut-off for tool-free cartridge changes. Suits households wanting easy installation and filtered drinking water without a tank.

Waterdrop Waterdrop 15UA (15UA Single-Stage Under Sink Filter)
US
£46.15 16000 gallons 0.75 gpm PFAS,PFOA/PFOS,lead,chlorine,heavy metals,sediment,odour,taste Easy; push-to-connect installation, 3 minute setup 1 year 10-125 psi

The Waterdrop 15UA is a single-stage under-sink ultrafiltration system certified to NSF/ANSI standards that delivers up to 16,000 gallons of filtered water at 0.75 gpm. It reduces PFAS, lead, chlorine and other common contaminants, installs quickly with push-to-connect fittings, and suits homeowners or renters who want a low-maintenance countertop-alternative for cleaner tap water.

Cloud Water Cloud RO (Tank-Based Under Sink Reverse Osmosis System)
US
£445.94 Pre/Post Filters 500 gallons, RO membrane 1,500 gallons 600 GPD 200+ contaminants (removes PFAS, heavy metals, fluoride, VOCs, pharmaceuticals) DIY-friendly; 30-60 minutes (requires faucet hole and drain hookup) 1 year

Cloud RO is a compact under-sink RO system with a built-in battery pump, remineralization, app monitoring, and NSF/ANSI 58 certification. It suits households wanting high contaminant reduction with faster flow and straightforward DIY installation.