Richard Arconti 
Waterdrop reverse osmosis systems have become extremely popular due to their innovation and reputation for building high-quality water RO solutions using NSF-certified filters. In this Waterdrop reverse osmosis system review guide, I’ll share everything you need to know about the company and a few of the current favorites that we’ve tested and installed.
About Waterdrop
Waterdrop is one of the leading manufacturers of water filtration systems in the U.S. The company was founded in 2015 with the purpose of providing safe and healthy water drinking water solutions. They now offer a broad product assortment but are best known for their RO systems.
I personally appreciate their offerings because they are more eco-friendly and are constantly pushing to incorporate the latest technology available. But best of all, they come at a reasonable price.
“We love our new Waterdrop RO system. It’s already saved us money since we are no longer buying bottled water, and I am so glad to reduce our use of single-use plastics as well. The water tastes great and the system works like a dream.”
Lisa M – Verified Buyer
🏆Waterdrop Reverse Osmosis System Review
- Undersink RO: G3 Tankless Reverse Osmosis System With UV Sterilizing Light
- Countertop RO: K19 Countertop Reverse Osmosis System
- Budget Choice: G2 Reverse Osmosis System
G3 Reverse Osmosis System
G3P800 Reverse Osmosis System Best Tankless
High efficiency with minimal wastewater
High 800 GPD flow rate water production
Remineralization filter to add healthy minerals
| Water Production | 800 GPD |
| NSF Certified | Yes |
| Filtration Stages | 3 Stage |
| Drain Ratio | 3:1 |
Overview
The Waterdrop G3 uses the latest filtration technology to provide purified drinking water on demand while incorporating many features that are not offered anywhere else on the market. Importantly, the filters have been tested to NSF standards 58 for the reduction of TDS (98%), lead (>99%), fluoride (99%), and many other harmful contaminants. This particular unit is available in both an 800 GPD and 600 GPD option depending on your water requirements.
I installed this undersink system to test the filtration effectiveness, production rate, and wastewater ratio firsthand. Let me first walk through what is included and how the system works.
This system is a top choice for best reverse osmosis systems in 2023.
System Components
- System Housing: The system housing measures 18.06” (L) x 5.65” (W) x *17.75” (H). Because this is a tankless system, it takes up very little space under your sink.
- Sediment Carbon Block Filter: The sediment filter lasts up to 6 months or 550 gallons before replacement. And since it’s a carbon block it won’t channel like granular carbon filters, which reduces effectiveness over time.
- Activated Carbon Filter: The carbon filter lasts up to 12 months or 1,100 gallons before replacement. It is made with coconut shell activated carbon block so it is highly effective at removing city water contaminants.
- Reverse Osmosis Membrane Filter: The RO membrane will last up to 24 months. Importantly, it is able to achieve 3:1 drain ratio so it wastes minimal water.
- Smart Display Faucet: The smart display is super unique for an RO system. You get real-time TDS readings, filter life, and water quality updates right on the faucet.
- UV Sterilizer Light: The included LED lamp will automatically turn on as water flows to sterilize up to 99.9% of microorganisms.
- Remineralization Filter: The remineralization filter is optional if you want to have the ability to add back 18 natural minerals like calcium, magnesium, and zinc.
- Installation Kit: The great thing about this system is it comes with all the install components and is easy to set up. This means you won’t need professional installation or have to buy additional parts.
How The System Works
The G3 RO has three filtration stages. It starts with water flowing through a scale-inhibitor layer to reduce water scale (hardness). Next comes the pre-carbon block filter to remove sediment, chlorine and chloramines which helps protect the RO membrane in the next stage.
The RO membrane has 7 layers of semipermeable membrane with pores that are only .0001 microns in size to remove thousands of common city water contaminants. Water is forced through the reverse osmosis membrane so that only pure H2O molecules can pass through while impurities are flushed away. This increases its ability to reduce contaminants like:
- Chlorine & Chloramine
- PFAS, PFOAS, PFOA
- Flouride
- Heavy Metals (Lead, Arsenic, Chromium)
- Volatile Organic Compounds (VOCs)
- Pesticides & Herbicides
- Nitrate & Nitrite
In the third stage, water passes through the post-activated carbon block filter. This filter finishes the water and removes any remaining impurities before the water is dispensed.
As the water flows to the dispensing faucet, the UV light turns on to sterilize viruses and bacteria that may be lingering in the drinking water. The end result is water that is up to 99% free of contaminants – more pure than bottled water!
Additionally, if you want to remineralize the water after it’s filtered, all of the systems can be paired with a remineralization filter. This is an extra filter that can restore minerals that are removed in the filtration process.
My Thoughts
From my experience testing a lot of RO systems, the G3 is the best tankless option. Aside from the exceptional filtration performance, it includes a lot of details that are overlooked by the competition.
The 800 GPD flow rate allows you to fill a cup in about 5 seconds. The smart faucet display is aesthetically appealing in any kitchen, but it also shows you all data right there without having to look under your sink at the unit (or most units don’t provide that filter life or water quality readings at all). Lastly, it wastes almost no water which is a big problem with traditional RO units.
K19 Countertop Reverse Osmosis System
K19 Reverse Osmosis System Best Countertop
Effective 4-Stage filtration process
High efficiency with minimal wastewater
Large 170 oz. storage tank
Overview
The K19 is the latest countertop offering from Waterdrop. It packs the performance of an undersink RO unit in a compact system that requires no installation. If you are renting a home or can’t modify your plumbing, these countertop ROs are the best option.
I set up and tested this system using a before and after lab test with Los Angeles tap water. The setup was very easy and the filtration results were impressive. For example, it was able to remove 100% of the worst contaminants like arsenic, lithium, and uranium.
See Full Lab Test Results For The Waterdrop RO:
- Untreated Water: See Lab Results
- RO Treated Water: See Lab Test Results
System Components
- System Housing: The system housing measures 13.8” (L) x 7.9” (W) x *16.3” (H). Because this is a countertop system, it takes up very little space and can be moved around with ease.
- Filter Cartridge: The filter lasts up to 12 months or 1,000 gallons before replacement. And since it’s all in one, you only need to replace the one filter cartridge which saves a lot on maintenance costs.
- UV Sterilizer Light: The included LED lamp will automatically turn on as water flows to sterilize up to 99.9% of microorganisms.
How It Works
The K19 uses one filter cartridge that consists of 3-stages. The first stage is a PP cotton membrane, followed by a carbon block filter, and lastly the RO membrane. After the water is filtered, it passes through the UV purification light to destroy bacteria and viruses.
The system is able to treat contaminants like:
- Fluoride
- Chlorine
- Heavy Metals
- Total dissolved solids (TDS)
- Viruses and bacteria
- Bad tastes and odors
To set the countertop reverse osmosis system up, simply insert the filter into the top of the unit and twist it into place. Then fill up the water storage tank with your tap water. Plug it in and allow it to run the start-up process. And that’s it! You can have purified drinking water in under 15 minutes.
The smart display will indicate the TDS levels, filter life, and the preset water volume. What I really like is it comes with 4 preset dispensing settings so you can fill up your cups or water bottles with one touch.
My Thoughts
The K19 has everything you would want in a countertop RO unit. It is compact, yet effectively removes harmful contaminants from your drinking water while using minimal waste water. I also liked that it has a large 170 oz. water storage tank so you don’t have to fill it up all the time. Lastly, the UV light is a great addition that is rare in countertop systems.
G2 Reverse Osmosis System
G2 Undersink Reverse Osmosis System Best Budget
Effective 4-Stage filtration process
High efficiency with minimal wastewater
Large 170 oz. storage tank
Overview
The Waterdrop G2 reverse osmosis system is the best budget option if you’re looking for a tankless undersink unit. Although it lacks some of the features of the larger G3, it still brings a lot of great functionality to the table. The two-stage filtration process is capable of removing toxic chemicals like disinfection byproducts, vinyl chloride, PFAs, and more. While the water production rate of 600 GPD is more than enough for the average family.
There are even some advantages to this model like the smaller size will take up less space under your sink. And since it uses two filters rather than three, the replacement costs are a little less expensive.
System Components
- System Housing: The system housing measures 17.3” (L) x 5.9” (W) x *13.9” (H). Because this is a more compact system, it will take up less space.
- Sediment Carbon Block Filter: The sediment filter will last 12 months or 1,100 gallons before replacing. The unique 2-in-1 filter uses a sediment membrane and an activated carbon block.
- Reverse Osmosis Membrane Filter: The RO membrane will last up to 24 months or 3,300 gallons. The membrane has pores that are .0001 microns and is able to achieve 2:1 drain ratio so it wastes minimal water.
- Brushed Nickel Faucet: The included faucet has a sturdy metal construction with a brushed nickel finish that looks great in any kitchen.
- Remineralization Filter: The optional remineralization filter can add back 18 natural minerals like magnesium, calcium, and zinc.
- Installation Kit: The G2 comes with all the installation components and can be set up in under 30 minutes. This means you can save on professional installation and won’t have to buy additional parts.
How It Works
The G2 utilizes a 2-stage filtration process. The first stage is a composite filter that combines a PP membrane and carbon block layer. This removes sediment and chlorine to protect the RO membrane in the next stage.
The reverse osmosis membrane has pores 0.0001-micron in size. Water is forced through the membrane allowing only pure H2O molecules to pass while blocking nearly all impurities. Lastly, the post-activated carbon filter polishes the water by removing bad taste and odors before dispensing the water.
Since this model does not include a smart faucet display, it features filter life indicators on the face of the unit itself.
My Thoughts
The G2 is an excellent budget option that has everything you would need without some of the conveniences included in the larger G3 model. This model does not include the smart display faucet or UV purification light. Nonetheless, it still performs exceedingly well and has a 2:1 drain ratio which is better than most competitors’ tankless units.
RO System Comparison Table
| G3 P800 RO | K19 Countertop RO | G2 P600 RO | |
|---|---|---|---|
| Requires Installation | Yes | No | Yes |
| Flow Rate | 800 GPD | 75 GPD | 600 GPD |
| Drain Ratio | 3:1 | 3:1 | 2:1 |
| Filter Life | Pre: 6 Mos. RO: 24 Mos. Post: 12 Mos. | RO: 12 Mos. | Pre: 12 Mos. RO: 24 Mos. |
| Annual Filter Replacement Cost | $145 | $60 | $75 |
Waterdrop RO Installation
All of the undersink tankless reverse osmosis systems come with the necessary hardware to install on your own. The installation process should take no more than one hour. The only additional tools you will need to complete the installation is:
- Variable speed drill
- 1/4” Drill bit for drainpipe
- 1⅜” Drill bit for faucet hole
- Adjustable wrench or pliers
- Screwdriver
- Utility knife
- Flashlight
Detailed installation instructions will be included, but you can also watch the tutorial video for step-by-step directions. Below is a diagram showing the configuration of the tankless system.
Filter Replacements
The filter replacements for both countertop and undersink RO systems are very simple. They are designed to be twisted on and off in a few seconds. Simply use your hand to rotate the old filter counterclockwise to remove it. Take your new filter and insert it into the housing, then twist it clockwise until it locks into place.
Before replacing the filters on a tankless unit, turn your cold water supply valve off under your sink. After you have swapped out the filters, slowly turn on the water supply and check for any leaks from the RO unit.
The reverse osmosis system filters will last between 6 – 12 months depending on which filter and unit you have. Replacement filter sets can be purchased directly on the Waterdrop website.
Key Considerations For Waterdrop Reverse Osmosis
Here are some key factors to consider when you are looking for the best RO filtration system for your home.
- Water Source: Whether you have well water or city water will impact your decision for selecting an RO system. All of the Waterdrop tankless and countertop ROs are designed for municipal water, so if you have well water, you will need a system specifically for well water. You might be able to get away with using a Waterdrop system on well water if you have a whole house filter and good pre-filtration before the RO system.
- Installation: Undersink RO units require a little bit of installation and plumbing modifications. If you either cannot make those changes or don’t want to deal with installation, the countertop RO will be the best choice.
- Budget: Sticking to your budget is important when shopping for your reverse osmosis filtration system. Prices vary for each option depending on features, filtration, NSF certifications, and production rate. See which features are a requirement for your needs, and which ones you can live without as you compare the available options.
- Tank vs Tankless: Tankless systems are relatively new and have a lot of advantages over traditional tank-based options. Tankless take less space, provide unlimited water on demand, waste less water, and have better technology features. The downside is they require electricity and aren’t ideal with well water.
Frequently Asked Questions
Does Waterdrop filter remove bacteria?
Is Waterdrop a good RO system?
How long do waterdro pfilters last?
Why Trust Freshnss
Ricky is the founder of Freshnss and product reviewer specializing in water filtration, home, and kitchen products. For this Waterdrop reverse osmosis review, he worked with our water review board of experts. And also with our network of industry professionals who offered reverse osmosis system insights and the qualities that made Waterdrop stand out from the competition. He looked into Waterdrop’s BBB accreditation and they have no complaints and a “B+” rating. Overall, the Waterdrop products stood out based on filtration performance, water production, warranty, and overall value. He has read thousands of user reviews, and written hundreds of product reviews. He has also tested and re-tested some of our top picks, and looked for filtration companies for new home water treatment options worth trying.
