RO 2550 4-Stage Reverse Osmosis System | Under-Sink Drinking Water Filter

Trusted RO filtration delivering cleaner, better-tasting water with NSF-certified performance.

Overview

The Pentek RO-2550 is a trusted 4-Stage under-sink Reverse Osmosis system manufactured by Pentair Water, one of the world’s most respected water treatment companies.

Compact, efficient, and NSF/ANSI Standard 58 certified, the RO-2550 is an excellent choice for homeowners who want premium, lab-certified water filtration without unnecessary complexity or high maintenance.

With proven performance and a complete installation kit included, this system from Pentair Water integrates seamlessly into home and apartment kitchens, as well as refrigerator or ice maker lines.

⭐ Why Homeowners Choose the RO-2550

✅ NSF/ANSI Standard 58 Certified

Independently tested for the reduction of TDS (Total Dissolved Solids) and a wide range of contaminants including lead, fluoride, chromium, radium, and more.

✅ Designed & Manufactured by Pentair (Pentek)

A U.S.-based global leader in residential and commercial water treatment.

✅ Complete Under-Sink System

Includes a treated 2.8-gallon storage tank, carbon stages, sediment filter, membrane, faucet, and full installation hardware.

✅ High-Quality TFC RO Membrane

The heart of the system — engineered to reduce dissolved solids and impurities for clean, crisp drinking water.

✅ Easy, Space-Saving Installation

Fits neatly under most sinks and supports optional refrigerator or ice maker connections.

✅ Smart Automatic Shut-Off Valve

Stops water production when the tank is full to save water and extend membrane life.

💧 4-Stage Filtration Process

Stage 1 | Sediment Filter
Captures sand, silt, rust, and particulate matter to protect downstream filters.

Stage 2 | Carbon Block Pre-Filter
Reduces chlorine & chemical impurities that can affect RO membrane performance and taste.

Stage 3 | TFC RO Membrane
The heart of the system — reduces dissolved solids, fluoride, heavy metals, and other impurities (as certified under NSF 58).

Stage 4 | Carbon Post Filter
A final polishing stage that enhances clarity & taste to produce fresh, clean drinking water.

🔬NSF 58 Certification

The Pentek RO-2550 is certified by the National Sanitation Foundation International for the reduction of:

• Barium

• Cadmium

• Chromium VI & III

• Copper

• Cysts

• Fluoride

• Lead

• Radium 226/228

• Selenium

• Turbidity

• Total Dissolved Solids (TDS)

This third-party validation ensures reliable, trustworthy performance.

⚠️Source Water Requirements

To ensure proper system performance:

• Pressure: 40–100 PSI

• Temperature: 40–100°F

• TDS: < 1,000 ppm (mg/L)

• Turbidity: < 1 NTU

• Hardness: < 10 gpg recommended

• Chlorine: Within municipal standards (carbon protects the membrane)

If you use well or rural water:
A water test is recommended. If biological contamination is present (coliform/E. coli), pair this system with a point-of-use UV sterilizer to neutralize microorganisms.

🔧Installation Overview & Replacement Schedule

Installation Overview:

• Fits neatly under most sinks

• Includes all hardware, tubing, and adapters

• Long-reach chrome faucet included

• Optional refrigerator/ice maker connection

• DIY-friendly design, or install via a handyman/plumber

What's Included:

• Pentek RO-2550 filtration assembly

• TFC RO membrane

• Sediment + carbon pre-filter

• Carbon post-filter

• 2.8-gallon treated storage tank

• Long-reach chrome faucet

• Tubing, fittings, and adapters

• Installation hardware

• User instructions

Replacement Schedule:

Stage 1 – Sediment Filter
📅 Every 6 months

Stage 2 – Carbon Pre-Filter
📅 Every 6 months

Stage 3 – RO Membrane
📅 Every 2–3 years

Stage 4 – Carbon Post Filter

📅 Every 6 months