OF 3DM Rings (0.5L)

Brand: OF

Revolutionary Aquarium Biological Filter Medium

OF® 3DM Pro-Filter Medium is a revolutionary mineral based beneficial-bacteria medium that incorporates the most advanced heating and multi-staged manufacturing techniques and technology to create this super macro-porous and tough biological filter medium.

It’s recommended for aquarist seeking the ultimate aquarium biological filter medium.


  • Improves Water Quality. Perfect medium to establish Nitrogen Cycle and help eliminate Ammonia, Nitrite, Nitrate and to prevent other poor water quality related diseases.
  • Tough and Macro-Porous. Advanced manufacturing and high temperature processes has given OF® 3DM Pro-Filter Medium their distinctive lightweight, tough and porous structure. Within the tough exterior lies 3 dimensional cavities of various spatial apertures (micro, medium and large cavities) all interlinked by micro-tunnels.
  • Ideal Bacteria Conditions. Continuous cavities and interlinked micro-tunnels increase the overall effective surface area of and create ideal conditions for billions of Aerobic and Anaerobic Bacteria within a single filter medium. The result is a faster bacteria colonization time, stable and longer bacteria life span.
  • Largest Effective Surface Area. BET Method surface area analysis has determined the effective surface area of OF 3DM Pro-Filter Medium to be in the range of 2550m² / litre, far surpassing other biological mediums in the market.
  • pH Neutral. pH-inert material does not modify pH; suitable for soft-water, brackish, hard-water and marine fish.
  • Flaking of Bio-membrane. Fine exo-skeletal deposits and organic particulates will accumulate and reduce your filter medium’s effective surface area over time. OF 3DM Pro-Filter Medium introduces the concept of bio-membrane flaking that minimizes the clogging of cavities and micro-tunnels.
  • Longer Water Retention Time. OF® 3DM Pro-Filter Medium increases the passage time of water within the filter with help from the cavities and micro-tunnels. This will greatly upgrade the capabilities of your biological filter by prolonging the water treatment period.
  • Environmentally Friendly. OF® 3DM Pro-Filter Medium can also be reused for horticulture purposes due to high mineral content and non-toxicity.


  • Surface Area/Volume : 2550m²/L (effective surface area)
  • Porosity : 40 – 75%
  • Water Absorptivity : 30 – 78%
  • Volume Density : 0.30 – 1.25g/cm³
  • Spatial Aperture Range : Micro (0.10 – 10µm), Medium (10 – 500µm), Large (0.1 – 3mm)
  • pH : 7 – 7.5
  • Percolation Rate : 0.2 – 0.6cm/sec
  • Conductivity : 40 – 145 (ppm)
  • Cavity Structure : Continuous 2 – 3 dimensional cavity
  • Density Range : >0.30 <0.60