20 Inch Big Blue CTO Carbon Block Water Filter – Features & Benefits
The 20 inch Big Blue CTO (Chlorine, Taste, Odor) Carbon Block Filter is engineered for effective reduction of chlorine, taste, odors, and various organic contaminants in drinking water. Constructed from activated carbon compressed into a dense block, this filter delivers high contact time and superior adsorption compared to granular carbon. Its Big Blue (4.5″ diameter) size provides increased surface area and dirt-holding capacity, making it ideal for whole-house, commercial, and pre-reverse-osmosis applications. Compatible with all standard 20″ Big Blue housings, the CTO carbon block filter helps protect downstream systems and enhances overall water quality. Replace regularly for consistent performance.
Sizing Guide
- Whole House Systems: 20″ Big Blue CTO blocks are excellent where chlorine taste/odor is a priority post-sediment stage.
- Pre-RO Stage: Use after a sediment filter to prevent carbon fouling.
- Flow Considerations: Big Blue cartridges support higher flow rates with lower pressure drop compared with 10″ cartridges.
Timing Recommendations
| Water Quality | Change Interval |
| Light use, low chlorine | ~9–12 months |
| Moderate use/municipal chlorine | ~6–9 months |
| Heavy use/strong odor | ~4–6 months |
Features An 20 Inch Big Blue CTO Carbon Block Filter:
- 5um filtration
- Highly effective filtration of water for certain VOC’S, chlorine, taste, and odour.
- Low-pressure drop. High-pressure performance.
- Extra dust holding capacity.
- Greater solids holding capacity.
- No leaching carbon ash.
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