Granular activated carbon and carbon block both use activated carbon, but the way the media is arranged changes the water pathway, pressure drop and cartridge behaviour.
How granular activated carbon works
Granular activated carbon, often called GAC, uses loose carbon granules to create a treatment bed. Water moves through spaces between the particles while adsorption occurs on and within the carbon.
Bed depth, granule size, flow distribution and contact time influence performance. Poor flow distribution can allow some water to take an easier path through the media.
How carbon block is different
A carbon block forms activated-carbon particles into a solid cartridge structure with a binder or another manufacturing process. The structure can influence water pathways, particle capture and pressure drop.
Sintering is another route for forming a solid carbon structure. None of these manufacturing labels proves universal superiority by itself.
Contact time, flow and capacity
A cartridge must provide enough media and a useful water pathway for the treatment role. Faster flow can shorten effective contact. Finer structures can increase resistance. Adsorptive capacity changes as more water passes through the filter.
That is why useful specifications include rated flow, capacity, pressure conditions and the exact reduction claim.
Media evidence is not finished-system evidence
NSF explains that adsorption and filtration claims are verified for defined products and standards. Supplier data for raw carbon can help describe a material, but it should not be stretched into a claim for every cartridge or complete system.
Which format is better?
Neither format wins every application. The better choice is the one engineered and tested for the required substance, flow, capacity, pressure and service interval.
Next: explore CarbonWeave™, compare treatment roles in the Filtration Guide, or ask WAA for a recommendation.