Brightwell Aquatics Xport NO3 Dimpled Filter Brick 9" x 4.50" x 2.50"

Use one XPort NO3 Brick for every 1,000 U.S. gallons ( 3,800 L ) of system capacity, more for heavy bio loads. Allow to stand overnight and then add the seeded XPort NO3 Brick to your system. You may also add the water back to your aquarium, if desired.

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