Went to calculate pond matrix vs sera siporax to see which was better:
Sera siporax:
1 liter sera siporax provides as much settling area for bacteria as approximately 34 liters of ceramic filter material. Therefore 1 liter sera siporax ensures more than 200 liters of biologically clean aquarium water.
Pond matrix:
Use 1–2 Liters of Pond Matrix™ for each 100 US gallons.
Both bio media does not ever need to be replaced. Either way, you can not go wrong these choices...
Sera siporax:
1 liter sera siporax provides as much settling area for bacteria as approximately 34 liters of ceramic filter material. Therefore 1 liter sera siporax ensures more than 200 liters of biologically clean aquarium water.
Pond matrix:
Use 1–2 Liters of Pond Matrix™ for each 100 US gallons.
Both bio media does not ever need to be replaced. Either way, you can not go wrong these choices...