I have had a tank for roughly a week. Did everything to set it up. Went and got my water tested at Petsmart and got the all clear. I put a peacock cichlid in (water was a little cloudy). A day after I put the fish in there was white gooey looking stuff at the bottom of the tank on the gravel. The cloudiness of the water is starting to disappear, but the more gooey looking stuff at the bottom of the tank has increased. What is it and will it hurt the fish?