Brightwell Aquatics Xport Bio Brick

Designed to be used in marine and hard freshwater aquariums with a pH of 7.5 or over
Highest porosity and largest useable surface area, per unit weight or volume, of all filtration media available anywhere
Provides huge amounts of aerobic and anaerobic surface area for efficient bacterial colonization.
Laboratory Tested: Provides over 71,000 square feet (6,596 square meters) of surface area per liter of medium. One brick has about 100,000 square feet of useable surface area for bacterial colonization.
When properly colonized, and used as directed, it will reduce toxic ammonia and nitrites to near zero in ponds and all aquariums, marine or fresh.
Also reduces phosphate significantly and dissolved organics.
Works excellently as the only filtration medium for the aquarium or pond or may be employed in addition to other filtration media.
Doped with Aragonite to buffer pH at the bacteria level, preventing acid buildup which eventually would kill the bacteria and reduce capacity. (Which is what happens in competing products)