Pentair Pentek EP-20BB Big Blue Carbon Water Filter - Whole House

In this review the Pentair Pentek EP-20BB is examined as a whole-house replacement carbon block cartridge for homeowners and light commercial users who want noticeably better chlorine taste and odor reduction. The bottom line: this 20 in x 4.5 in cartridge delivers strong chlorine and taste removal with a high dirt-holding design and a long nominal service life, making it a practical choice when replacing a Big Blue or other heavy duty housing cartridge. The review focuses on ease of fit, filtration performance, and value for money based on product specs and user feedback.

Key Features

• Superior chlorine reduction: The bonded powdered activated carbon media provides greater chlorine taste and odor reduction than competitive 10 carbon blocks, improving drinking and cooking water quality.
• Universal fit for Big Blue housings: Sized at 20 in x 4.5 in so it fits all 20 in Big Blue or other heavy duty housings and easily replaces other 20 in x 4.5 in carbon cartridges.
• High porosity design: A high porosity structure helps prevent premature plugging so the cartridge maintains low pressure drop while using more of the carbon adsorption capacity.
• Pre-filter protection: A polyolefin bilaminate pre-filter traps sediment that commonly clogs carbon blocks, extending useful life and reducing maintenance frequency.
• Long service capacity: Tested and certified by NSF International and rated to treat up to 44,000 gallons before replacement under typical conditions.

Who It's For

The EP-20BB is aimed at homeowners, food service operators, and small commercial users who need a reliable whole-house carbon block that fits standard 20 in Big Blue or heavy duty housings and prioritizes chlorine taste and odor reduction. It is also appropriate for households dealing with sediment, sulfur, or mild iron issues when used as part of a multi-stage system.

It is less suitable for systems that require sub-micron particulate filtration alone or for users who need a tiny under-sink cartridge; those users should look for dedicated sub-micron filters or under-sink specific replacement cartridges. Also, if incoming water has very heavy particulate loading, a more aggressive sediment pre-filter stage may be needed first.

Pros & Cons

Pros

• Effective at removing chlorine taste and odor and improves water taste for cooking and drinking.
• Good value and long service life with a 44,000 gallon rated capacity and durable construction.
• High porosity and the bilaminate pre-filter reduce plugging and help maintain flow.
• Tested and certified by NSF International for assurance of performance.

Cons

• Some users report mixed experience with water pressure, so households sensitive to any pressure drop should monitor performance after installation.
• Not intended as a standalone solution for heavy iron or sulfur without additional targeted treatment in high-concentration situations.

Specifications

Brand	Pentek
Model	EP-20BB
Size	20 in x 4.5 in
Media	Bonded powdered activated carbon
Rated Capacity	44,000 gallons
Certification	NSF International tested and certified
Compatibility	Fits all 20 in Big Blue and heavy duty housings

Our Verdict

The Pentair Pentek EP-20BB is a dependable whole-house carbon block replacement that excels at chlorine taste and odor removal while offering long service life and broad compatibility with 20 in Big Blue housings. For most households looking to improve water taste and reduce chlorine without frequent cartridge changes, it represents good value; those with extreme water chemistry issues should combine it with targeted pre-treatment.

Frequently Asked Questions

How often should this cartridge be replaced?
Replace every year or when you notice a drop in water pressure or water quality, depending on usage and feed water conditions.

Will it fit my existing housing?
The cartridge is 20 in x 4.5 in and fits all 20 in Big Blue or other heavy duty housings designed for that size.

Does it remove sediment as well as chlorine?
The bilaminate polyolefin pre-filter traps sediment to extend life, while the carbon block primarily removes chlorine taste and odor and some contaminants; heavy sediment may require an upstream sediment filter.