What should I look for when buying filtration types compared?

Start with a water test. Buy filtration for contaminants actually in YOUR water. Sediment + carbon is the standard two-stage setup for most issues. RO is overkill if your only concern is chlorine taste.

What are common mistakes when buying filtration types compared?

Buying RO when simple carbon would address the issue. Skipping sediment pre-filter -- particles clog downstream filters. Expecting carbon to remove lead or fluoride -- you need RO.

Filtration Types Compared

Buying Guide

Created by Ryan Pietrzak Illinois Licensed Plumber · In the plumbing industry since 2009

Updated February 20, 2026

Key Takeaway

Different contaminants require different filtration technologies. No single filter removes everything. Understanding what each technology does and does not do helps you build the right system.

Overview

Different contaminants require different filtration technologies. No single filter removes everything. Understanding what each technology does and does not do helps you build the right system.

What to Know

Sediment Filters

Remove particles: sand, silt, rust, debris. Rated by micron size (5 micron standard, 1 micron fine). First stage in any multi-stage system. Does not remove chemicals, bacteria, or dissolved contaminants. $5-15 per cartridge.

Carbon Filters

Remove chlorine, chloramine, VOCs, pesticides, taste and odor. Most common home filtration. Does not remove dissolved minerals, fluoride, or bacteria. $10-30 per cartridge, change every 6-12 months.

Reverse Osmosis

Removes 95-99% of dissolved contaminants including lead, fluoride, arsenic, nitrates. Multi-stage system. Produces purified water at dedicated faucet. Wastes water (3-4:1 ratio standard). $150-400 for under-sink.

UV & Specialty

UV: kills 99.99% of bacteria and viruses. Essential for well water. Does not remove chemicals. Iron/manganese filters: specialized media for well water. Water softeners: ion exchange removes hardness but is not a filter.

Comparison

Sediment: particles only, $5-15/cartridge, first stage

Carbon: chlorine/chemicals/taste, $10-30/cartridge, most common

RO: 95-99% of dissolved contaminants, $150-400 system, most thorough

UV: bacteria/viruses, $300-800 system, essential for wells

Softener: hardness minerals, $800-2500 system, ion exchange

Buying Tips

Start with a water test. Buy filtration for contaminants actually in YOUR water.
Sediment + carbon is the standard two-stage setup for most issues.
RO is overkill if your only concern is chlorine taste.
UV is non-negotiable for private well water.

Common Mistakes

Buying RO when simple carbon would address the issue.
Skipping sediment pre-filter -- particles clog downstream filters.
Expecting carbon to remove lead or fluoride -- you need RO.
Installing UV without pre-filtration.

Bottom Line

Test first. Sediment + carbon for most city water. RO for lead, fluoride, or maximum purity. UV for all well water. Layer technologies based on specific contaminants.