A good biofilter needs a lot of surface area with open spaces between for good aerated water flow. A high surface area is useless if the passageways are so small that water flow cannot penetrate. Green Matala cleans very easily by simply shaking the pieces out before using a garden hose to spray them clean. Green Matala is available in full sheets, 48" x 39" x 1.5" . Ships folded once to allow UPS delivery. Folding does not compromise effectiveness of the filter pad.