E.S.V. Granular Activated Carbon 3.5-lbs.
The E.S.V. Granular Activated Carbon,
based on bituminous coal, provides the best combination of pore size,
large particle size, high surface area, low ash, and hardness for
chemically filtering aquarium water. In addition, test results indicate
no leaching of phosphates. The high hardness level of this carbon
prevents the dispersion of particles throughout the aquarium which can
occur with softer grades of carbon. The large particle size facilitates
water movement through the carbon and helps prevent the removal of
planktonic food organisms via mechanical filtration.