iSpring RO800G Tankless Reverse Osmosis System - High Flow 800 GPD

In this review of the iSpring RO800G tankless reverse osmosis system, the bottom line is simple: this unit is for households or small commercial sites that need high-capacity, point-of-use purified water without the footprint of a storage tank. The main reason to buy is its tankless design combined with an exceptional 2.5:1 pure-to-drain ratio, which delivers instantly filtered water while using far less waste water than many traditional RO systems. The system also includes a brushed nickel faucet and simple DIY-friendly servicing that appeals to homeowners who want cleaner tasting water without complex maintenance.

Key Features

• Tankless design: Provides instant filtered water under the sink without a storage tank, saving space and eliminating wait time for replenishing a reservoir.
• High capacity flow: Delivers up to 0.6 GPM and is rated 800 GPD, making it suitable for busy kitchens, offices, or light commercial use where steady output matters.
• Water-saving technology: Achieves a 2.5:1 pure-to-drain ratio, using significantly less wastewater than older RO designs and reducing overall water consumption.
• Two-stage filtration: Combines a PP+CTO composite prefilter to remove sediment and chlorine with an 800 GPD RO membrane that reduces TDS, fluoride, PFAS, and heavy metals.
• Easy maintenance: Quick-connect fittings and twist-and-lock filters allow tool-free installation and filter changes, and the unit includes filter life reminders for convenience.
• Built materials and support: Constructed from food-grade, BPA-free materials and backed by a one-year limited warranty plus lifetime technical support from a U.S. team.

Who It's For

The iSpring RO800G is best for families, small offices, coffee shops, or anyone who needs a continuous, higher-volume source of purified water under the sink and values a compact footprint. It suits users who prioritize water savings, faster flow than many residential RO units, and ease of DIY installation and service.

Those who should look elsewhere include buyers who need a dedicated water feed for a refrigerator or ice maker, since the manufacturer notes refrigerated connections are not recommended, and consumers who prefer multi-stage systems with separate mineral or remineralization stages built in.

Pros & Cons

Pros

• Excellent drinking water quality with reliable reduction of TDS and contaminants thanks to the 800 GPD RO membrane.
• Space-saving tankless design that delivers filtered water instantly and fits neatly under most sinks.
• Simple installation and filter replacement with quick-connect fittings and twist-and-lock cartridges make it DIY-friendly.
• Water-saving 2.5:1 pure-to-drain ratio lowers wastewater compared to many traditional RO systems.

Cons

• Some users report mixed experiences with actual flow rate; performance can vary by household water pressure.
• Not recommended for connecting to refrigerators or ice makers, which limits some installation options.

Specifications

Product type	Tankless under-sink reverse osmosis system
Rated capacity	800 GPD (system rating)
Maximum flow	Up to 0.6 GPM
Pure-to-drain ratio	2.5:1
Filtration stages	2-stage (PP+CTO composite prefilter, 800 GPD RO membrane)
Faucet	Brushed nickel designer faucet (lead-free)
Materials and support	Food-grade BPA-free materials, 1-year limited warranty, lifetime technical support

Our Verdict

The iSpring RO800G is a practical choice for anyone who needs high-volume, under-sink purified water with minimal space impact and lower wastewater. It offers strong contaminant reduction, quick flow for routine kitchen use, and straightforward DIY servicing, making it good value for busy households or small commercial sites that do not require refrigerator hookup or multi-stage remineralization.

Frequently Asked Questions

Can this be used with a refrigerator or ice maker?
It is not recommended for refrigerator or ice maker connections, so plan separate supply options for those appliances.

How difficult is installation?
Most users can install the unit DIY using the included quick-connect fittings and tutorials; no plumber or special tools are required for typical setups.

Does it save water compared with older RO units?
Yes, the tankless design and a 2.5:1 pure-to-drain ratio reduce wastewater compared with many traditional RO systems.