Product imagery from Sentry H2O.
Sentry H2O Wellness System Replacement Filters
A spent filter quietly stops protecting you.
Free Ground shipping on every order, contiguous US. No minimum.
Usually ships within a week. Sentry H2O ships orders on Mondays and Thursdays.
Order detailsDualGuard · City water
- Filter set
- $120
- Total
- $120
- Plug & play
- 30-day returns; restocking fees apply
- Filters & filter media are consumables
- Free Ground shipping on every order, contiguous US
- Checkout hosted by Shopify
- Lifetime product support
Why it matters
The Wellness System Replacement Filters, in short.
Don't let a spent filter quietly stop protecting you. Exact-fit DualGuard 2-filter or TriGuard 3-cartridge (ToxyGuard + AlkaGuard + BioChemGuard; replace all three together) sets for city or well water — replace at 3,000 gallons or 1 year, whichever comes first, and you're covered. The 500-gallon mark is peak-performance context. Choose the filter grade and water source that match your system.
The details
Specifications
Specifications reflect the manufacturer (Sentry H2O). See our Science page for published independent lab reports and testing gaps. We do not call the complete systems NSF certified: Sentry H2O uses tested or certified components where applicable.
Sentry H2O · Replacement filters
Sentry H2O Wellness System Replacement Filters
Sentry H2O systems are built to last years — the filter change is what keeps them performing like day one. Subscribe once and the exact set arrives every 12 months at 10% off, or buy a one-time set.
Subscribe & save is selected in the purchase options above: every 12 months at 10% off. One-time purchase is there too.
Eligible purchase options are shown above; if subscription is unavailable, choose a one-time purchase.
Straight answers
Common questions
Is the Sentry H2O Wellness System Replacement Filters right for my home?+
Sentry H2O Wellness System owners. Not sure? Our 60-second quiz confirms fit in a minute.
How often do filters need replacing?+
3,000 gallons or 1 year, whichever comes first. Auto-ship on the refill page renews the exact refill every 12 months at 10% off; replace sooner if your usage reaches the rated gallons first.
What if it is not right for me?+
Contact Mountain Pure Water first at (435) 990-3778; we issue the return instructions before you send anything back. Eligible refills may be returned within 30 days after delivery; restocking fees apply. Filters and filter media are consumables; see our Shipping, Returns & Refunds policy for the full terms.
How do I handle a return, shipping damage or a warranty claim?+
Contact Mountain Pure Water first at (435) 990-3778 with your order number and details of the issue; include photos for shipping damage. We coordinate the review and issue any return instructions, including the correct destination. Wait for our instructions before sending anything back. Shipping damage, including broken fittings, is reviewed case by case. See our Shipping, Returns & Refunds policy for the 30-day return window, restocking fees and warranty terms.
Is shipping free?+
Free Ground shipping on every order, contiguous US. No minimum. Shipping is $10 to Alaska, Hawaii and Puerto Rico. We ship to US addresses only. See our Shipping, Returns & Refunds policy for details.
What is catalytic-carbon filtration, and how is it different from reverse osmosis?+
Catalytic-carbon filtration uses specially processed activated carbon that reacts with and breaks down contaminants as water passes through multiple stages. Unlike reverse osmosis, our Sentry H2O systems don't strip the water of everything -- they target the bad stuff while leaving naturally occurring beneficial minerals in place. The non-RO city filtration stages produce no RO reject-water waste.
Does the system need electricity or produce wastewater?+
Our non-RO city filtration stages run on water pressure and produce no RO reject-water waste. UV accessories require power. Well treatment may produce waste or backwash water; requirements depend on the selected configuration.
Real customers, real water
Review evidence for this product
Product relevance is stated explicitly; unrelated excerpts are never substituted.
Sentry H2O store review snapshot, independently collected by Judge.me, as of August 2026.
Reviews of this product, then its product family
The first 2 reviews are for this exact product; the others cover products in the Wellness System family. Each card names the product reviewed.
August 2026 review-count snapshot.
Rating, count and verification rate checked on Judge.me September 15, 2026.
See the Sentry H2O store reviews →Review of SENTRY WELLNESS SYSTEM REPLACEMENT FILTERS
Second year
We've had the under-sink filter for the last year, and it was easy to buy a replacement for year 2.
Review of SENTRY WELLNESS SYSTEM REPLACEMENT FILTERS
Filters
The customer service team was very helpful since we forgot what kind of filters that we needed. The filters replacement came very quickly and easy to install the replacement filters. The water tastes better than the water from refrigerator.
Review of SENTRY WELLNESS SYSTEM
Awesome water system!
We absolutely love the Sentry H2O water system. Both my husband and I were skeptical at first, thinking that the water would still have a fun taste…We were wrong—it tastes great! Easy to install and fast delivery!
Review of SENTRY WELLNESS SYSTEM
Satisfied
We love the system, water tastes great . Quick shipping too. No more buying and handling 5 gal water jugs .
Review of SENTRY WELLNESS SYSTEM
Happy customer
I called to order and told them what I needed including tubing length. They asked me to place the order on the web. They texted me to fix a mistake I made and the order came in correct. Installation was a breeze. I love the water.
Review of SENTRY WELLNESS SYSTEM
In love
I love love my new system. We put in a water spout to use for now. Replaced a distillery system so saving time and aggravation. And the water tastes good.
Review of 1/4" Dedicated Faucet Connection (Direct RO Replacement)
It works great and easy to install.
Review of Peace of Mind Shut-Off Valve
Highly recommended
Don't order without it!
Know your water
Know what is in your water before you choose a system.
Start with independent findings for your area, then match your home to the right Sentry H2O system.
Read your local water report
Your area's annual Consumer Confidence Report (CCR) lists what has been detected in your municipal tap water.
Salt Lake City? See what's really in your water →Check the EWG Tap Water Database
Enter your zip code for a plain-language breakdown of the contaminants found in your local supply.
Open the EWG database →At-home test kit (for well water and specific concerns)
Use our mail-in well-water kit when an individual result makes sense for your source or concern.
Shop the well-water kit →Want help matching the result to a Sentry H2O system?