Understanding the Differences Between Common Water Filter Replacements

When it comes to keeping your water clean, healthy, and great-tasting, the right replacement filters make all the difference. Each filter type is designed to target specific contaminants or improve certain water qualities, so knowing their differences helps you get the best performance out of your system.

Below, we break down the most common water filter replacements — what they do, when to use them, and the benefits of each.

1. ACB — Activated Carbon Block Filters

What They Do:
Activated carbon block (ACB) filters are highly effective at removing chlorine, volatile organic compounds (VOCs), and bad tastes or odors. Their dense structure also captures small particles.

Best For:

• City water where chlorine and chemical taste are a concern
• Improving water for drinking and cooking

Advantages:

• Excellent chlorine removal
• Fine filtration down to 0.5–5 microns
• Better taste and odor in water

Considerations:
They can clog quickly in high-sediment water, so using a sediment filter before an ACB is recommended.

2. Ceramic Filters

What They Do:
Ceramic filters use a porous ceramic surface to physically block bacteria, protozoa, and sediment. Their fine pores can filter particles down to 0.2–0.5 microns, making them excellent for microbiological protection.

Best For:

• Camping, hiking, and emergency water filtration
• Well water or surface water sources where bacteria may be present

Advantages:

• Highly effective against bacteria and protozoa
• Long-lasting and cleanable surface
• No electricity or chemicals required

Considerations:
Ceramic filters do not remove viruses unless paired with additional treatment. They also have a slower flow rate than other filter types.

3. Coconut GAC — Granular Activated Carbon (Coconut Shell) Filters

What They Do:
Coconut shell GAC filters remove chlorine, improve taste, and reduce organic chemicals in water. They’re known for their high adsorption capacity and eco-friendly material.

Best For:

• Final “polishing” of drinking water
• Taste and odor improvement after other filtration stages

Advantages:

• Excellent taste improvement
• Renewable, natural filtration material

Considerations:
GAC filters do not remove sediment as effectively as carbon block filters, so they work best when paired with pre-filtration.

4. CRK — KDF/Carbon Combination Filters

What They Do:
CRK cartridges combine KDF media with activated carbon to target chlorine, heavy metals (like lead, mercury, and iron), and to inhibit bacterial growth inside the filter.

Best For:

• Well water with metal content
• Municipal water that needs both chemical and microbial control

Advantages:

• Dual-action filtration for a wider range of contaminants
• Long filter life when used properly

Considerations:
CRK filters cost more than basic carbon filters and require proper water flow for best results.

5. Iron/Manganese Filters

What They Do:
These filters use specialized media to oxidize and trap dissolved iron and manganese, preventing staining and metallic tastes in water.

Best For:

• Well water with visible staining or metallic taste
• Protecting appliances and plumbing from iron buildup

Advantages:

• Effectively reduces iron and manganese
• Prevents red, brown, or black staining on fixtures

Considerations:
Requires periodic backwashing or media replacement. Not effective for high levels of hydrogen sulfide unless combined with other treatments.

6. KDF-Only Filters

What They Do:
KDF (Kinetic Degradation Fluxion) filters use copper-zinc alloy media to reduce chlorine, heavy metals, and control bacteria growth in the filter.

Best For:

• City water with chlorine and metal concerns
• Extending the life of downstream carbon filters

Advantages:

• Inhibits bacterial growth in the filter
• Removes dissolved heavy metals like lead and mercury

Considerations:
Works best with warm to hot water in certain applications. Often combined with carbon for broader filtration.

7. Multi-Media Filters

What They Do:
Multi-media filters layer different filter materials (such as gravel, sand, anthracite, and garnet) to remove a wide range of sediment sizes from water.

Best For:

• High-turbidity water sources
• Pre-treatment for commercial or industrial systems

Advantages:

• High sediment-holding capacity
• Long time between backwashes

Considerations:
Requires backwashing to maintain performance. Does not remove chemical contaminants.

8. PF — Pleated Filters

What They Do:

Pleated filters capture sediment such as dirt, rust, and other large particles in your water. Their folded (pleated) design increases the surface area, allowing them to trap more debris before needing replacement.

Best For:

• General sediment removal in well or municipal water
• Protecting downstream filters from clogging

Advantages:

• Large dirt-holding capacity for longer filter life
• Some pleated filters are washable and reusable

Considerations:
Pleated filters are excellent for coarse filtration, but they aren’t designed to remove fine particles, chemicals, or odors.

9. pH/Alkaline Filters

What They Do:
pH/alkaline filters use mineral media to raise water pH and add beneficial minerals like calcium and magnesium, improving taste and alkalinity.

Best For:

• Reverse osmosis systems where water is slightly acidic
• Taste enhancement for drinking water

Advantages:

• Balances acidic water
• Adds healthy minerals

Considerations:
Will not filter out contaminants. Mineral content and pH increase depend on water chemistry.

10. Post-Carbon (Polishing) Filters

What They Do:
Post-carbon filters provide a final polishing stage, removing any residual taste or odor after primary filtration, especially in RO systems.

Best For:

• Final stage in drinking water systems
• Ensuring fresh-tasting water from RO units

Advantages:

• Improves taste right before dispensing
• Removes any residual storage tank odors

Considerations:
Must be replaced regularly for best results. Limited contaminant removal beyond taste and odor.

11. RO Membrane — Reverse Osmosis Membrane

What They Do:
RO membranes use semi-permeable material to remove up to 99% of dissolved salts, metals, and many contaminants, including fluoride, nitrates, and some bacteria.

Best For:

• Drinking water purification
• Areas with high TDS (total dissolved solids)

Advantages:

• Extremely effective contaminant reduction
• Long lifespan with proper pre-filtration

Considerations:
Slow filtration rate, requires a storage tank. Produces wastewater during operation.

12. SED — Polypropylene Sediment Filters

What They Do:
Polypropylene melt-blown sediment filters remove dirt, sand, silt, and rust particles from water. They are commonly used as a first-stage filter in multi-stage systems.

Best For:

• Pre-filtration in well and city water systems
• Protecting sensitive downstream filters

Advantages:

• Inexpensive and widely available
• Effective at various micron ratings (1–20 µm)

Considerations:
They are disposable and can clog quickly in high-sediment water, requiring more frequent changes.

13. String-Wound Sediment Filters

What They Do:
String-wound filters trap sediment in a depth-layered pattern, allowing them to hold more dirt before clogging. They’re ideal for water with heavy particulate content.

Best For:

• Well water with visible particles or turbidity
• Applications requiring a high dirt-holding capacity

Advantages:

• Excellent for high-sediment conditions
• Available in a wide range of micron sizes

Considerations:
Not washable, and in rare cases, fibers can shed into the water if the filter is damaged or overused.

14. UV Filter — Ultraviolet Disinfection

What They Do:
UV filters use ultraviolet light to deactivate bacteria, viruses, and other microorganisms without chemicals.

Best For:

• Well water or surface water with microbiological risks
• Final stage after sediment and carbon filtration

Advantages:

• Chemical-free disinfection
• Effective against bacteria and viruses

Considerations:
Requires electricity and annual lamp replacement.Does not remove particles or chemicals.

Choosing the Right Replacement Filter

The right replacement filter depends on your water source, the contaminants you need to remove, and your filtration system’s design. In many multi-stage systems, filters are used in combination or sequence to get the most benefits.

Regularly replacing your filters is essential for keeping your water clean, safe, and great-tasting. Discover quality replacement filters at PRO+AQUA.