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Brightwell Aquatics

Xport BIO Blocks Freshwater - 2 inch Biological Filtration Media - Brightwell Aquatics - 3 pack


Ultra-porous Biological Block Media with Superior Performance Characteristics

Biological filtration in aquariums is one of the most important methods of filtration, naturally performed by nitrifying bacteria. In order to thrive, though, this beneficial bacteria must have a surface area for it to colonize which can include rocks, gravel, filter, or other solid objects. Increasing the surface area for bacteria to colonize greatly increases their ability to reduce potentially harmful elements in the aquarium such as ammonia, nitrites, phosphates and dissolved organics. With the Xport BIO Blocks a 1.5" block contains approximately 4,000 square feet of surface for the bacteria to colonize, making it one of the most compact and efficient bio medias ever.


  • For use freshwater aquariums with a pH of 7.5 or over
  • Highest porosity and largest usable surface area, per unit weight or volume, of all filtration media available anywhere
  • Provides vast surface area for aerobic and anaerobic bacterial colonization
  • Over 40,000 square feet (3,716 square meters) of surface area per liter of medium.
  • One 1.5” block has about 4,000 square feet of usable surface area
  • Reduce toxic ammonia and nitrites to near zero in ponds and freshwater tanks, when proper colonized and used per guidelines
  • Significantly reduces phosphate 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)

Instructions & Guidelines:

  • Use one 1.5" XPort Bio Block for every 20 to 40 U.S. gallons ( 75 to 150 L ) or one 2.0" Xport Bio Block for every 30 to 50 U.S. gallons ( 100 to 200 liters) of system capacity, more for heavy bio loads.
  • Rinse material very well with aquarium water or purified tap water.
  • For superior results, seed the material using FlorinBacter, MicroBacter7 or MicroBacterCLEAN, as appropriate for your aquarium, by placing XPort Bio Block in a plastic container, filling it with aquarium water, and then adding the full recommended dose of either bacterial product, based on the size of your aquarium, to that container.
  • Allow to stand overnight and then add the seeded XPort Bio Block to your system.
  • Discard water.
  • It is recommended that you use sponge, fine filter floss or other mechanical filtration ahead of XPort Bio Block to prevent clogging with organic material.
  • For maximum results, also provide a good carbon source for growing bacteria, such as Brightwell Katalyst bio pellets, liquid Reef BioFuel or Florin Axis, as appropriate for your aquarium, as directed on their label.
  • Do not fluidize or allow to churn!

Additional Information

You can use more blocks than the capacity shown above, however, we recommend that you do not exceed 5 times the recommended number of blocks. For nitrification, or removal of ammonia and nitrite, employing the brick aerobically, or above the water line will provide maximum results. To do this, mount the brick in air, above the water level, and run a small stream of water through the brick. It is not necessary to run the whole flow of the main system pump through the block. A flow of about 40 to 80 liters per hour is ideal. An adjustable flow control will allow you to adjust the water flow to only that which will flow through (and not around) the block. On the other hand, removing nitrate is an anaerobic process and limiting oxygen to the block as much as possible will maximize the nitrate removal. In this case, mount the block beneath the water surface in the sump in a very low flow area, if possible.

To use one block for both aerobic nitrification and anaerobic denitrification, mount the brick below the water surface and provide medium flow around it. The bacteria growing in the top 1/4" of the surface of the brick will be aerobic and will use up all the oxygen so that the inside of the brick goes anoxic or anaerobic. Anaerobic denitrifying bacteria will then colonize the internal surfaces of the brick and you will get both nitrification on the surface and denitrification in the internal parts.

One important criteria in marine systems is gas exchange. Xport is the best bacterial media in the world, but it is not good at gas exchange. Bio balls are the best for gas exchange, so any system will work better with a small stack of bio balls placed in the main flow (in air).

Manufacturer Info

Brightwell Aquatics Aquarium Supplies
The goal of Brightwell Aquatics is to provide the absolute highest quality, scientifically-sound products and customer service of any aquarium water care manufacturer, and to do it all in a straight-forward and honorable fashion. All Brightwell products are formulated by marine scientists with a passion for the aquarium hobby. They utilize the highest purity ingredients in concentrations that provide the most use to hobbyists. Nearly all Brightwell Aquatics products are over 99.9% pure. The usage guidelines of Brightwell Aquatics products are written in plain language but the company is always available to answer consumer questions. All products are lot numbered for quality control and customer service.

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BW2985 Xport BIO Blocks Freshwater - 2 inch Biological Filtration Media - Brightwell Aquatics - 3 pack // Brightwell Aquatics InStock 29.99 USD 0.0 0