I've used both and I don't know if either works, or even to what degree.
Both products provide surface area for nitrifying and denitrifying bacteria. there is no exact recipe for surface area per tank, for biological filtration. it will vary tank to tank. so I wouldn't worry so much about the right amount - there is no "right" amount.
Both products provide surface area for nitrifying and denitrifying bacteria. there is no exact recipe for surface area per tank, for biological filtration. it will vary tank to tank. so I wouldn't worry so much about the right amount - there is no "right" amount.


