Waterdrop TSU 0.01m Ultra-Filtration Undersink System - Tankless

In this review of the Waterdrop TSU 0.01m Ultra-Filtration Under Sink Water Filter System, the bottom line is clear: this is a practical choice for households on municipal cold water who want better tasting, safer drinking water without losing beneficial minerals. The system is designed as a three-stage, tankless undersink unit with a 0.01 um ultrafiltration membrane and a dedicated faucet; it does not reduce TDS and is not suitable for well water or hot water. For people who want simple installation, no wasted water, and long filter life, this unit delivers.

Key Features

• 0.01 um ultrafiltration membrane: Captures most harmful particles larger than 0.01 um, reducing residual chlorine, taste and odor, and many contaminants while keeping minerals.
• Retains essential minerals: Keeps calcium, potassium, sodium and magnesium in the water so mineral content and mouthfeel remain intact even after filtration.
• Integrated waterways: Built-in waterway design prevents leakage and allows filter replacements without shutting off the water supply.
• Smart panel indicators: LED indicators notify when to replace filters so users can maintain water quality without guesswork.
• Long service life: Main ultrafiltration element is rated up to 24 months, lowering replacement frequency and ongoing cost compared with short-life cartridges.
• Tankless, no wastewater: Operates without a storage tank or electricity and produces no wastewater, making it efficient and space-saving under the sink.

Who It's For

This system is best for homeowners or renters with municipal cold water who want an undersink filter that improves taste and removes chlorine, fluoride traces, and many contaminants while keeping beneficial minerals. It suits kitchens where space under the sink is limited and a dedicated stainless steel faucet is acceptable, and for users who prefer a tankless design with no running wastewater.

It is not appropriate for users on well water, anyone needing hot water filtration, or shoppers who expect a reverse osmosis system that lowers TDS and removes dissolved solids. If you need a filter that reduces total dissolved solids or treats well water, consider other technologies instead.

Pros & Cons

Pros

• Easy installation with included stainless steel faucet and hoses, and filter changes by twist-and-pull in seconds.
• Noticeable improvement in taste and odor noted by users, with preserved mineral content for a natural mouthfeel.
• Long main filter lifespan and smart indicators reduce maintenance hassle and replacement frequency.
• Tankless design with no wasted water and no power required makes it efficient and compact.

Cons

• Does not reduce TDS, so those relying on a TDS meter will see little change and may be disappointed if they expect RO-level purification.
• Requires drilling a 1 in hole in the countertop for the faucet, which may be a barrier for some renters or certain countertops.

Specifications

Filtration stages	3-stage tankless system
Membrane pore size	0.01 um ultrafiltration
Suitable water source	Municipal cold water only
Main filter lifespan	24 months (PP 6 months, CT 12 months)
Installed components	Stainless steel faucet, 3/8 inlet hose, 1/4 outlet hose, feed adapter
Wastewater	No wastewater generated
Power required	None

Our Verdict

The Waterdrop TSU undersink ultra-filtration system is a strong value for anyone on municipal cold water who wants improved taste, reduced chlorine and common contaminants, and preserved minerals without the complexity or water waste of reverse osmosis. It is easy to install, has long filter life and smart indicators, but it is not a match for well water or buyers seeking lower TDS readings.

Frequently Asked Questions

Will this system reduce TDS?
No. This ultrafiltration system retains dissolved minerals and will not lower TDS measurements.

Can it be used with hot water or well water?
No. It is designed only for municipal cold water and is not suitable for well water or hot water.

How often do filters need replacing?
The main ultrafiltration element is rated about 24 months; the PP prefilter is about 6 months and the CT stage about 12 months under typical municipal use.