ill tell you why people are saying these bad things because in the back of their minds they know the substrate is really only a good storage place for detrius, thats why top discus breeders dont use it, and they already spent money on there substrate and really dont want to go threw the trouble of removing it, i only keep substrate with fish who play with it like my frontosa to take away there substrate would be a sin but my black rhom seems fine w/o it and hes got alot of filtration 1000 gph on a 60 gallon tank hes growing really fast so if you have a cichlid who plays with substrate dont do it ,if you have a rhom or any other fish not interested in playing do it now.