i have a 55 gal. aquarium and i have this kinda crappy looking (in my opinion) brown gravel in it that came with it when i got it used off craig’s list. i’ve been told that african cichlids like a sandy substrate rather than gravel. my old aquarium had dark gray/black gravel and i really liked the way it looked over the brown pee gravel that is in my 55. so i am trying to find black sand that is not going to cost $20 for a 10 lb bag like they sell at petsmart. one person told me to use pool filter sand because it is real cheap but it is still brown.