Specified From A Test
Media chosen from a water test, because sediment and taste are not the same problem.
Water Filtration Systems In Gaithersburg, MD
Whole-house water filtration systems in Gaithersburg — installed at the apex of the line, specified against a water test, with filter changes and servicing on a schedule.
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Filtration System Service in Gaithersburg
Whole-house water filtration in Gaithersburg
The county's civic water system is efficient and most residents have no complaint about it. But no system is perfect, and contaminants can get through — particularly in heavy rain, when the civic filters are working against volume they were not sized for.
A whole-house water filtration system sits at the apex of the water line and screens everything entering the house rather than one tap. That is what separates it from a jug or a faucet-mounted filter: the washing machine, the water heater and every shower are downstream of it.
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Whole House
At the apex of the line, so the heater and the washer are protected too — not just the kitchen tap.
Serviceable With Water On
Bypass fitted, so servicing it never means the house is without water.
Taste, sediment or staining in the water? One test settles it.
Call (301) 804-6759Worth Knowing
Matched to what the test finds
Filtration is specified against what the test finds. Sediment, chlorine taste, iron staining and particulate all want different media, and a filter chosen without a test is a guess wearing a warranty.
It is also not a softener. Filtration addresses what is carried in the water; hardness is dissolved into it. Houses with both problems run both, in a deliberate order.
Treatment sequence
How a filtration install runs
Filters need periodic replacement. A technician checks the system and media and looks for pressure drops or developing faults.
Where a repair is needed we can schedule it rather than scramble, because a filtration fault is rarely an emergency. That is the difference between maintenance and a breakdown.
We test first
We test the supply. Sediment, taste and iron want different media, and the test is what chooses between them.
Specified from the result
The system is specified against the result rather than against a package, and sized to the house's flow.
Installed with a bypass
Installed at the apex of the line with bypass, so the house still has water while the system is serviced.
Changes scheduled
Filter changes put on a schedule — once or twice a year for most systems.
Why Mallick
Maryland Has Trusted Mallick For 30+ Years
WSSC-licensed and insured crews, and warranties in writing: one year on installations, 30 days on repairs. The same standard whether it is a filtration system call at 2pm or a burst line at 2am.
Google reviews
2,979
4.9 average across Gaithersburg, Frederick and Woodbine
Ways To Save
Current Offers On This Job
$81
Off
Water Quality Installation
Limit 1 offer per customer, cannot be combined with other offers, residential use only, must be presented at time of service. Not applicable to dispatch charge. Valid Jan 1 – Dec 31, 2026.
Our maintenance plan
The Service Contract Of Choice
A 12-month annual maintenance contract for your home’s plumbing. The team is small enough to give you personalized attention and large enough to handle whatever comes up.
What stands behind every contract
12-month coverage term
24/7 emergency line
Licensed, trained technicians
Payment plans available
2-Year Extended Warranty for Furnished & Installed Equipment
6-Month Repair Warranty
Levels are matched to your home
The office confirms the current contract levels and details before you commit — call and the team will walk you through the options.
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Customer Field Notes
What Customers Remember After The Call
4.9
2,979 Google reviews across three Maryland locations
Field note 01 · Gaithersburg, MD
“Eric and Nick did a wonderful job.”
Very thorough and provided detailed explanation of what was needed to get our garbage disposal up and running.
Abbas and Koli were great technicians.
Quickly diagnosed the issue, thoroughly explained everything, and gave me a few options to move forward. I've had great experiences working with Mallick, highly recommend.
Chrissie Schenkel · Gaithersburg, MD Abbas came to our house for an emergency repair on a Saturday.
He was courteous and kind, he didn’t rush, and he worked hard to fix our problem and thoroughly investigate. It was hard to find a plumber who could do this on a Saturday at the last minute, and we appreciated Mallick’s and Abbas’s willingness.
Raj Nayak · Gaithersburg, MD Abbas Rahimiari was exceptionally professional, looking at our two plumbing problems, describing the underlying issues, fixing one immediately and explaining options on the other. Courteous, clear and efficient. And knowledgeable.
Gordon Schatz · Gaithersburg, MD I had a wonderful experience with Billy.
He was amazing and he was able to fix my issue with no concerns! 10/10! Thank you Billy.
Mia Barker · Gaithersburg, MD Excellent service and support from William Clem and Malick Plumbing.
Had a pinhole leak in a water service line. Found and fixed the problem … thanks so much.
Daryle Seckar · Gaithersburg, MD Roberto and Adelson were great to work with, efficient, and answered all questions. Top service and repair of water heater!
Jonathan Daly · Gaithersburg, MD
Fred and Luka were great!
They took the time to find the issue as well as helping me get opinions on future concerns as a new homeowner! Real experts and will work with them again!
Elijah Wadsworth · Woodbine, MD Abbas and Koli were fantastic.
They quickly identified and resolved our issue, and did a check to ensure there were no other sleeping issues. They were a pleasure to work with, respectful, and kind.
Kelley Barnaby · Gaithersburg, MD I received great service from both Ikem and CJ today.
They quickly identified the leak and fixed the issue. They also did a great job replacing some valves that needed replacing. They were very experienced and efficient. I have used Mallick several times and have always been pleased with their service.
Melissa Cavuto · Gaithersburg, MD Abbas and Erick were professional, knowledgeable and kind.
They inspected and guided me to make safe choices with my range that had a gas leak.
Andrea Huerta · Gaithersburg, MD Abbas and Bryan installed my new water heater.
There was a leak in my furnace and they fixed it also! The job was perfect. They had to install vents that were well done. They left no trace and the house was completely clean. The new water heater works like a charm. HIGHLY RECOMMEND this team and Mallick.
Janet · Gaithersburg, MD Kyle was so helpful in helping my husband and I fix the water pressure in our house. Kyle was very well versed and experienced, providing great options for future improvements to water filtering. I would highly recommend his services to anybody struggling with plumbing issues.
Azusena Herrera Tapia · Gaithersburg, MD
Every quote above comes directly from Mallick’s current Google Business Profile record.
Read more customer storiesCommon Questions
Filtration System Questions, Answered
Still Stuck?
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(301) 804-6759Someone picks up 24/7 — nights, weekends, and holidays included.
How do I know if I need a whole-house filter?
A metallic or chlorine taste, visible sediment, staining in sinks and tubs, or simply wanting protection against what gets through the civic system in heavy rain. A water test identifies what is actually present and decides the filter media — the answer is different for sediment than for taste.
Where is a whole-house filtration system installed?
At the apex of the water line, where the supply enters the house and before it branches. That is what makes it whole-house rather than point-of-use, and it is why the water heater and washing machine benefit as much as the drinking tap.
Is a filtration system the same as a water softener?
No — they solve different problems. Filtration removes what is carried in the water; a softener removes the dissolved minerals that cause hardness. Plenty of Gaithersburg homes need both, and the order they are plumbed in matters.
How often do the filters need changing?
Once or twice a year for most systems, depending on the media and how much sediment your supply carries. The early sign of an overdue change is a drop in pressure across the filter, which is easy to miss until flow noticeably falls off.
What should I look for in a water filtration company?
Ask whether they test before specifying, who changes the filters afterwards, and whether the install includes a bypass. A water filtration company that recommends a system without testing your supply is selling a product rather than solving your problem — and a system plumbed in without a bypass cannot be serviced later without cutting pipe.
Where We Work
Filtration System Service Across Maryland
Bethesda Rockville Silver Spring Germantown Potomac Olney Clarksburg Damascus Chevy Chase North Potomac Frederick Woodbine Columbia Ellicott City Aspen Hill Boyds Burtonsville Darnestown North Bethesda Poolesville Takoma Park Wheaton–Glenmont White Oak Green Valley Linganore Washington, DC College Park
Related Services
Water Quality Water testing, softeners, whole-house filtration, reverse osmosis and UV purification for Gaithersburg homes on county water and on private wells — specified from a test rather than from a catalogue.
Water Softeners Water softener installation, repair and servicing in Gaithersburg and Montgomery County — sized from a water test, installed at the apex of the line so every fixture downstream is protected.
Water Testing In-home water analysis for well and municipal water in Gaithersburg and the surrounding area. Understand hardness, chlorine, pH and other characteristics that affect everyday water use.