Waterdrop WD-TSB-ALK Slightly Alkaline Under-Sink Water Filter

Slightly: The Waterdrop WD-TSB-ALK is an under-sink alkaline water filter system with a dedicated faucet. It is described for cold municipal tap water and does not reduce TDS, so it is not a choice for buyers seeking TDS reduction or well-water filtration.

At a glance

Listing describes an alkaline system with three under-counter filters and a dedicated faucet.
The manufacturer says the filters reduce PFAS, PFOA/PFOS, fluoride, residual chlorine, heavy metals, taste and odor.
Listed for cold municipal tap water. The manufacturer says it does not reduce TDS and is not suitable for well water or hot water.
Replacement filters are identified as WD-10PP, WD-10GC and WD-10ALK, with the WD-10ALK specified for the alkaline stage.

Price

$117.88Save 21%

Reference price: ~~$149.99~~

Price checked: Nov 14, 2026

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Often bought together

Waterdrop TSB-ALK Slightly Alkaline 8 Layer Under Sink Water Filter System | Reduces PFAS, PFOA/PFOS, Fluoride, Chlorine, Bad

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Pros and cons

Pros

Dedicated faucet is listed, keeping filtered-water dispensing separate from the main sink faucet.
The listed 8,000-gallon capacity and 12-month filter life provide capacity and time-based replacement guidance.

Cons

Does not reduce TDS, limiting its suitability for buyers who specifically want dissolved-solids reduction.

Technical specifications

13 specifications

Identity
Brand	Waterdrop
Model	WD-TSB-ALK

Power and operation
Power configuration	Mechanical Water Pressure
Maximum flow rate	1.5 gpm
Supported water TDS level maximum	700

Dimensions and installation
Installation type	Under Sink
Dimensions listed	12.9"L x 4.3"W x 12.4"H

Materials and protection
Material listed	NSF/ANSI Approved Components

Filtration and maintenance
Purification method	Alkaline
Capacity	8000 gallons
Filter life cycle	12 months

Water conditions
Lower temperature range	35 °F
Upper temperature rating	100 °F

What to know before buying

The manufacturer specifies cold municipal tap water only, not well water or hot water. It also states that TDS is not reduced, and that listed TDS maximum is 700. Confirm replacement-filter compatibility and change intervals for your water and usage.

What’s in the box

Included

System ×1
Faucet ×1
3/8"–1/2" converter set ×1
Accessory kit ×1
Hose ×2

Who is it for?

A good fit for

Households with municipal cold tap water seeking a separate faucet and alkaline filtration.
Buyers who want a listed filter capacity and annual filter-life reference.

Less suited to

People using well water or seeking filtration for hot water.
Buyers whose primary goal is lowering TDS.

Waterdrop WD-TSB-ALK Slightly Alkaline Under-Sink Water Filter · photo 2 — Additional product photo 2

Customer reviews on Amazon

4.5 / 5 · 785 ratings

5 stars79%79%
4 stars9%9%
3 stars3%3%
2 stars2%2%
1 star7%7%

Aggregate customer ratings skew strongly positive, with most ratings in the five-star category, but a smaller low-star share means the figures alone do not explain individual experiences or establish why customers felt as they did. They offer a broad sentiment signal, not evidence about filtration performance or fit for a particular water source. The manufacturer's stated limits remain important, especially the lack of TDS reduction and restriction to cold municipal tap water.