when you do a water change, are you supossed to mix up the gravel so that you can get rid of the waste and stuff that is left in there? and i have 1 Electric Blue Ahli, 1 JD, 1 White Assorted African, 1 Pleco, and 1 Minnow type thing that doesn't appear to be a minnow since it is more agressive then all of my other fish. how often and how much water changes should i be doing? currently i am doing weekly 25% water changes. is that too little for the fish i have?
