Review: Express Water WH300SCKS Heavy Metal Whole House Water Filter

This page may contain affiliate links. If you buy a product or service through such a link we earn a commission at no extra cost to you. Learn more.

The Express Water WH300SCKS is a wallet-friendly whole house water filter that features a 3-stage filtration process.

The system was designed primarily for removing heavy metals from water and presents some enticing features like the transparent first-stage filter housing that allows you to confirm your filter’s state without dismantling the system.

We’ll analyze these and other features of the Express Water WH300SCKS and determine if it’s a worthy investment.

Express Water WH300SCKS Heavy Metal Whole House Water Filter

Express Water WH300SCKS Heavy Metal Whole House Water Filter

Price: $
Filter Media: Sediment (5 Microns), Catalytic Carbon, KDF, Carbon Block
Filter Life: 100,000 gal or 6-12 Months
Flow Rate: 15 gpm
Annual Cost: ~$170-340

Overall Rating: 4.0/5.0 ⓘRating based on filtration performance, filter life, price and yearly cost, NSF testing/certification, customer support, product warranty, our testing/experience, user feedback, and other factors.

Express Water WH300SCKS Heavy Metal 3-Stage Whole House Water Filter – All Specs

  • Model: Express Water WH300SCKS
  • Annual Maintenance Cost: ~$170-340
  • Filter Media/Process: 5-Micron PP Sediment, Catalytic Carbon, KDF85, Carbon Block
  • Filter Stages: 3
  • Flow Rate: 15 gpm
  • Filtering Capacity: 100,000 gal or 6-12 Months
  • WxHxD: 23.5″x29.25″x8.5″
  • Weight: 63 lb.
  • Water Temperature: 40-100 °F
  • Water Pressure: 45-80 psi
  • Fitting: 1″ Female NPT
  • Warranty: 1 Year

Express Water WH300SCKS – Key Features

Most importantly, the Express Water WH300SCKS Heavy Metal 3-Stage Whole House Water Filtration System includes a sediment filter, a kinetic degradation fluxion filter, and an activated carbon block filter.

With a 15 gpm flow rate, it can be used conveniently by both small and large households.

The 3-stage filtration process works like this:

  • Stage 1: A polypropylene sediment filter traps sediments down to 5 microns. It protects your plumbing, appliances, and subsequent filter stages from sand, rust, silt, dirt, and other sediments.
  • Stage 2: The kinetic degradation fluxion filter uses catalytic carbon and KDF85 filter media to remove iron, nickel, lead, mercury, and other soluble and potentially harmful heavy metals from water. It also removes chlorine, sulfur, and chloramine, and prevents microorganisms from accumulating.
  • Stage 3: The activated carbon block filter made from coconut shells captures leftover chlorine, pharmaceuticals, pesticides, odors, VOCs, and other chemicals.

All in all, you get filtered water that is much healthier and tastes a lot better – at every outlet in your home!

Product warranty? 1 year!

Express Water Heavy Metal Whole House Filter Pros

The Express Water WH300SCKS whole house filtration system is more affordable than most, so it’s perfect if you’re working on a budget.

What’s more, the first-stage filter housing is clear and allows you to detect that your sediment pre-filter is due for a change without dismantling the system.

But that’s not all. The system has pressure release buttons for each filter stage, making it easier to unscrew filter housings during cartridge replacements (it’s more difficult to remove the housings with pressure still in the system, so a pressure release button helps).

The Express Water also has pressure gauges for each filter stage (that’s 3 pressure gauges!). The gauges help you monitor your system’s performance and let you know which filters need changing and when.

There’s also some flexibility to be enjoyed here. Because the system comes with 20×4.5 inch (big blue) standard-sized filter cartridges, they can be replaced with off-brand models or other cartridges from Express Water (like the iron filter cartridge). So you can customize your system however you want and maybe even save money doing so!

And lastly, the standing stainless steel frame which can be used for ground installation vs using the mounting bracket. The frame also provides a protective shield around the system against accidental bumps.

What Contaminants Are Being Removed?

The Express Water whole house system removes sediments and dirt down to 5 microns. It also removes chlorine, pharmaceuticals, organic chemicals like VOCs, industrial solvents, and water-soluble heavy metals including lead, mercury, iron, and nickel.

It further removes bad taste and odor, pesticides, chloramine, and sulfur, and stops microorganisms from growing within the system.

Express Water WH300SCKS Heavy Metal Whole House Water Filter

The Express Water WH300SCKS – learn more on


Installing this system is a bit more complicated than usual because there’s no in-built bypass valve, and you have to install a bypass on your own (if you want one). Aside from that, there is no reason not to try to install this system DIY-style as long as you are handy with tools.

Please consider these instructions as a general guideline. Always make sure to check and follow your user manual before getting started.

Tools needed to install this system include:

  • Towels
  • Monkey wrench
  • Medium crescent wrench
  • Pipe cutter (this depends on the pipes used, e.g. hacksaw, ratchet cutter, wheel cutter)
  • Teflon tape
  • Plumber’s silicone grease

Depending on your plumbing setup, you may also need a soldering iron or torch power drill.

Parts you need include:

  • Shut-off valves (depending on your plumbing setup)
  • Pipe converter (1″ to ¾” or other)
  • Additional piping
  • Pipe hangers
  • Pressure protection or reducer valve

Note: Installation steps may differ depending on your home’s plumbing setup. You may need to use different pipes or fittings. If your water source is prone to sudden pressure spikes, you may also need to purchase a pressure protection/reducer valve.

The installation steps are detailed below:

  1. Shut off the main water line.
  2. Open faucets to drain the water and depressurize your plumbing.
  3. Prepare your install site (this could be at any point after the main water supply line enters your home but before the line branches or meets the hot water heater).
  4. Measure the amount of line you’ll have to take out at your install location (ensure there’s enough space for the system, adapters, shut-off and bypass valves, and any other fittings you might need).
  5. Cut the line and allow it to drain. The end of the line should be cut fine and with no jagged edges.
  6. Stand the system on its frame on the floor or mount it to the wall at the installation location. If you’re mounting, ensure your wall is strong enough to support the system’s weight when it’s full of water.
  7. Fix the valves, pipes, and fittings to each side of the system.
  8. After you complete the connections, slowly turn your main water valve back on and allow the system to fill up completely.
  9. Turn on a nearby cold water faucet to flush the system.
  10. Check your system and piping for leaks.

Note: The flushed water will appear darkish in color due to the loose carbon particles that are flushed out of the system. It could also be cloudy because of air bubbles getting forced out of the system and pipes. When you notice this, don’t be alarmed – it’s completely normal and temporary.

Keep the water running until it clears up, and then let it run for 5 more minutes. Wait for 30 more minutes, and then run the cold water for an additional 10 minutes. Your system is now ready for use!


The Package (Parts)

  • Mounting bracket with filter heads and stainless steel frame
  • FLTWH2045S1 sediment filter cartridge with housing
  • FLTWH2045K catalytic carbon + KDF filter cartridge with housing
  • FLTWH2045C1 activated carbon block filter cartridge with housing


Each filter stage of the Express Water heavy metal whole house filter is designed to last for 6-12 months (or 100,000 gallons of water). However, your filters may need to be replaced sooner (or later) depending on the quality of your water, your water usage, and factors like water temperature. If your home water pressure suddenly drops by 10-20 psi, it’s probably time to replace filters.

Annual replacement costs range from $170- $340, depending on how often you replace. The maintenance cost here is higher than with many other whole house water filters but still reasonable.

Here are step-by-step instructions for changing the filters:

  1. Turn off the system’s water supply and open nearby faucets until the flow stops (this depressurizes the system). Once the flow stops, close the faucets.
  2. Press the red pressure buttons and then unscrew the housings from your system using your filter housing wrench.
  3. Take out and discard the old filter cartridges. Then, drain any water that remains in the housings.
  4. Clean the housings by scrubbing the inside and top manifold with a gallon of warm water mixed with 1 tablespoon of household bleach. Do NOT directly add bleach to your system.
  5. Rinse all parts of the system until the smell of bleach is gone.
  6. Carefully remove the O-ring from each housing and lubricate it with silicone grease before putting it back in place.
  7. Lubricate the threads of the filter housings, too.
  8. Put a new filter into each housing (it must be facing the right direction; the carbon, KDF, or PHO filters should have their O-rings facing the top of the system).
  9. Screw on the housings into the top manifold.
  10. Tighten each housing with your hands, and give it a slight additional turn with your housing wrench (be careful not to overtighten).
  11. Turn on the water supply to the system.
  12. Flush your new filters by turning on a cold water faucet.


Here is a link to the official manual:

NSF and Other Certifications

There are no NSF certifications for this product as far as we can tell.

Earlier Product Versions

To our knowledge, this product does not have any earlier versions.

Express Water Heavy Metal Whole House Water Filter Cons

The first downside to the Express Water heavy metal whole house water filter is that there are apparently no NSF certifications for contaminant reduction, so you can’t completely trust that the filter removes all the listed contaminants.

Besides, the system is for low heavy metal levels only.

Also, it may be unsuitable for heavily contaminated water like most well waters. If you can recall, the Express Water filters are said to last 6-12 months, but users complained that theirs only lasted a few months before needing replacements. Obviously, this means more money spent on replacements and higher maintenance cost.

There have also been many complaints about a drop in water pressure after installing the system.

Finally, we would have preferred a built-in bypass.

Express Water WH300SCKS Review: Our Verdict + Best for

All in all, the Express Water WH300SCKS whole house water filter is solid for filtration of water with chlorine/chloramine and low levels of certain heavy metals like mercury or iron.

It’s reliable if you’re only trying to improve your water’s aesthetics, but if you have serious heavy metal contamination in your water, we recommend choosing a specialized filter like the Springwell WS for manganese/iron or the PIONEER for lead.

Our Rating in Detail:

  • Filtration Performance: 4.0/5.0
  • Filter Capacity (Life): 4.0/5.0
  • Purchase Price: 4.5/5.0
  • Annual Cost: 3.5/5.0
  • Overall: 4.0/5.0

Comparison to Other Whole House Water Filters

Let’s see how the Express Water filter measures up against a popular competitor, the SpringWell CF.

SpringWell CF Whole House Water Filter

SpringWell CF

Price: $$$
Filter Media: 5-Micron Sediment, Catalytic Carbon, KDF
Filter Life: 1,000,000 gal or 6 Years
Flow Rate: 9-20 gpm
Annual Cost: ~$40

Overall Rating: 5.0/5.0 ⓘRating based on filtration performance, filter life, price and yearly cost, NSF testing/certification, customer support, product warranty, our testing/experience, user feedback, and other factors.

Get 5% Off! Use Code: BOS5OFF

Express Water WH300SCKS Heavy Metal Whole House Water Filter

Express Water WH300SCKS

Price: $
Filter Media: Sediment (5 Microns), Catalytic Carbon, KDF, Carbon Block
Filter Life: 100,000 gal or 6-12 Months
Flow Rate: 15 gpm
Annual Cost: ~$170-340

Overall Rating: 4.0/5.0 ⓘRating based on filtration performance, filter life, price and yearly cost, NSF testing/certification, customer support, product warranty, our testing/experience, user feedback, and other factors.

The SpringWell CF (check our full review here) is a tank-based whole house filter system that also uses KDF filter media and catalytic carbon to remove contaminants like chlorine, chloramine, pesticides, PFAS, disinfection byproducts and more from water.

The reason why we prefer the SpringWell CF, however, is because it uses a lot more catalytic carbon and KDF, so it has higher reduction rates and can be better used where there’s heavy contamination.

The SpringWell also has a longer filter life (1,000,000 gallons or 6 years). Considering the maintenance cost of no more than $40 a year, the SpringWell is much cheaper to maintain in the long run, despite the steeper initial cost which is the system’s biggest downside – it costs between $1,000 to $1,750 (depending on the unit size chosen).

Also, let’s not forget that with SpringWell CF, you’re entitled to a limited lifetime warranty and a 6-month money-back guarantee if you are unsatisfied with the product. The Express Water system only offers a 1-year warranty.

In all, the SpringWell provides better filtration results, is cheaper in the long run, and lasts longer. In our opinion, it’s a healthier and more economical choice.

This completes our review of the Express Water Heavy Metal Whole House Water Filter. If you have any questions please don’t hesitate to leave a comment below!

About the Author Gene Fitzgerald

Gene Fitzgerald is one of the founders of BOS and currently head of content creation. She has 8+ years of experience as a water treatment specialist under her belt making her our senior scientist. Outside of BOS, Gene loves reading books on philosophy & social issues, making music, and hiking.
Learn more about .


Information provided on BOS is for educational purposes only. The products and services we review may not be right for your individual circumstances.
We adhere to strict editorial guidelines. Rest assured, the opinions expressed have not been provided, reviewed, or otherwise endorsed by our partners – they are unbiased, independent, and the author’s alone. Our licensed experts fact-check all content for accuracy. It is accurate as of the date posted and to the best of our knowledge.

Leave a Comment: