AC-30 Good Water Machine® Under Sink Water Filtration System

As low as $15/Per Month

Get delicious water on tap with the AC-30 Good Water Machine® Under Sink Water Filtration System. With powerful four-stage filtration and an optional water quality monitor in the faucet, this reverse osmosis water filter system provides unbeatable value and an unbelievable hydration experience.

Ready for a drinking water upgrade? Your local Culligan® water experts can help determine the right solution for your municipal or well water. Schedule your free, in-home water test or phone consultation to get started.

Get Life-Enhancing Water Filtration on Tap

Hydration on Demand

Instantly refill your cup and enjoy refreshing hydration all day long with cleaner, filtered water on demand.

Effortless Sustainability

Do your part to keep plastic waste out of landfills when eliminating single-use bottles of water.

Flexible to Fit Your Needs

Seamlessly integrate this under-sink reverse osmosis system into your home by choosing a tank size that best fits your space.

Affordable Quality

Get great-tasting filtered water for just pennies a glass, directly from your kitchen sink.

Certified Contaminant Reduction

With a four-stage filtration process, this reverse osmosis water filter system can reduce sediment and tiny particles that can make water cloudy while addressing elements like chlorine that cause unpleasant tastes and odors.








Radium 226/228


Hexavalent Chromium


Hexavalent Chromium


Hexavalent Chromium





Elevate Your Water Experience

The AC-30 Good Water Machine was built to fit your home’s needs. You can enhance your system with these additional options:

Designer Faucet

Choose from three modern faucets in white, brushed nickel or chrome to match your home’s interior.

Tank Size

Opt for a two-, three- or nine-gallon tank depending on the available space in your home.

Good Water Sentry™ Monitor

Know when to contact your dealer for service with this optional technology that continually monitors the RO filter for optimum operation.

ClearLink PRO™

Use your existing faucet to switch between RO and tap water at the touch of a button. The display also shares information on filter life and water quality.


100% Satisfaction Guarantee

If you are dissatisfied with your Culligan product for any reason within 30 days of your purchase, Culligan will remove the product and refund the purchase price.


Third-Party Certified

The Culligan Good Water Machine1 has been tested and certified by WQA to NSF/ANSI 372, and CSA B483.1, and NSF/ANSI Standard 58 for the effective reduction of TDS, Barium, Cadmium, Hexavalent and Trivalent Chromium, Lead, Radium 226/228, Copper and Selenium as verified and substantiated by test data.​ Learn more about product certifications here.

Ready To Take the Next Step?

Schedule a free, in-home consultation and water test to get one step closer to the soft water your family deserves. With options to buy, finance or rent, your local Culligan water expert will make recommendations based on your home, water usage, test results and any other concerns.

Our Environmental Impact


40 Billion+ Bottles Saved

Culligan water filtration solutions benefit the environment by reducing single-use plastic bottle waste and saving billions of bottles each year.


Earth-Conscious Innovation

We prioritize sustainability in designing and developing new products.


Global Water Leadership

Culligan has joined the CEO Water Mandate and the Water Resilience Coalition to lead the way in positive, global water stewardship.


Culligan products are reliable and long-lasting, with industry-leading warranties. The AC-30 Good Water Machine has a limited lifetime warranty, excluding the replaceable filter cartridge and RO membrane. The RO membrane and filters have a one-year warranty

To access customer support, call your local Culligan water expert or​ fill out this Maintenance & Support form​.


AC-30 Good Water Machine® Under Sink Water Filtration System

Diameter x Height

2-Gallon Tank / 9 in x 14 in
3-Gallon Tank / 11 in x 14 in
9-Gallon Tank / 15.5 in x 24 in


40 – 120 psi

Water Temperature

33° – 100° F

Daily Production Rate

14.5 (54.88L)

Recovery Rate


Filter Cartridge


Particle Filter (1)

1 year

Advanced Carbon Filter (2)

1 year

Polishing Filter (4)

1 year

RO Membrane Filter (3)

Dependant on water quality

Our unmatched, white-glove service doesn’t stop at your free water test and consultation. Your local Culligan water experts will be there to help for the entire life of your water softener with installation and maintenance, assisting with needs such as salt refills, system sanitation and more. They can even monitor your system proactively for issues, offering you further peace of mind.


Convenient Service Plans

Sign up for our regular salt delivery and maintenance plans so you never have to worry about your system’s performance.


85+ Years of Experience

With over 85 years of water treatment experience, you can count on us to provide the solutions and service you need anytime.


Unwavering Local Support

Our team of experts knows your local water and is there to offer support and services right in your neighborhood.


Flexible Installation Areas

Your system can be installed anywhere you have access to main water piping, a drain and an electrical outlet — in the laundry room, basement, garage, or outside.

What can I expect when installing the AC-30 reverse osmosis water filter system?

Your local Culligan water experts are there to make installation simple. First, they’ll connect your system to your water line and a nearby drain. Then, depending on your selection, your faucet or ClearLink PRO will be set up. As a last step, your local Culligan Water experts will test the performance and demonstrate how to operate the system, so you can enjoy your upgraded water immediately.

With its compact design and virtually unlimited water supply, the AC-30 Good Water Machine is a great choice for homeowners and renters — just make sure your landlord approves it.

You can purchase replacement filters or parts through your local Culligan water experts, who can also handle changing and maintaining them.

To keep your reverse osmosis water filter system performing well, you should have your system sanitized and your filters changed approximately every year. That said, ​service frequency may vary depending on local water conditions and water usage. Your local Culligan water experts can do all of this for you; many offer service packages to make it even easier.  

Installation costs will depend on where the system is being installed and other factors. To get more details about costs, please contact your local Culligan water expert for more information.

Costs can vary depending on a variety of factors, including which accessories you select. After your local Culligan water expert tests your water and you determine the best solution for your home, they will be able to give you an accurate quote for options to buy, rent or finance.

Getting an under-sink reverse osmosis system is one of the ways to treat drinking water for a wide range of potential contaminants2. It might be necessary to combine systems and solutions to get higher-quality water. However, it’s best to start with our free, in-home water quality test to figure out exactly what your well may need.

Yes, but they likely are not as comprehensive. While many standard refrigerator, faucet and pitcher filters rely solely on carbon filtration, it’s only one of multiple stages of filtration that typical RO systems use to make tap water cleaner, safer and better tasting. For one of the most in-depth, targeted approaches to filtration, reverse osmosis systems are the best choice.

What does an AC-30 Good Water Machine under-sink reverse osmosis system filter out?

A Culligan reverse osmosis system gives you high-quality drinking water, expert installation and maintenance, industry-leading warranties, proven durability and a 30-day guarantee. The Culligan water team can confidently guide you toward the best systems for your needs and will be there through the life of your product.

Yes – with the ClearLink PRO wireless accessory, you can use your existing faucet and switch between RO and tap water with the touch of a button. Culligan RO systems are the only reverse osmosis systems that give you the option to use your existing tap. Better yet, you don’t need to drill additional holes in your countertop.

RO systems filter contaminants from water by forcing them through a semipermeable membrane to separate contaminants as small as a single atom. Most RO systems also include additional stages of filtration, including sediment and carbon filters.

Yes, you can download the owner’s guide here:

Download Owner’s Guide

An RO system can be installed anywhere that has access to a cold water line and drain — such as a basement, crawl space or in an adjacent cabinet. This includes any size or type of home, apartment or condo. If you are renting, it is advised to check with your landlord before installing any water treatment system.

The AC-30 Good Water Machine requires a water pressure minimum of 40 psi to properly operate; most homes should be at or above this level. If you do have lower water pressure, a booster pump can enable usage of this system. If you’re unsure whether your water meets that requirement, contact your local Culligan water experts, who have extensive knowledge about local water conditions.

We feel our water is much healthier to drink & cook with

especially after viewing the filters that were removed last month!!

— Thomas & Michelle P, TN

It is a better alternative to buying bottled water.

Good to know that a Culligan technician is available at any time for filter service when needed.

— Darwin R, NY

We have had it for years and wouldn’t be without it.

We would recommend Culligan to friends, family and neighbors.

— Alexa A, ON

Let’s Get Started

Start enjoying the benefits of soft water in your home with help from your local Culligan water experts.