I have one male GBR in a 29g, with neon tetras and cory's. My ph is 6.8, Kh 3*, Nitrates stay below 20 before I water change, temp set at 80*F. I've had him for about a year now. When I first got him he was shy, and for two weeks, only ate blood worms... But then a few weeks later he turned into the king of the tank, and eats anything he can fit into his mouth... and chases off anything in his line of site when hes trying to eat...