I have a 1500 gallon aquarium built into the side of my house with a 4'x4' viewing window inside, my question is can anyone give me some help on some colorful fish that I can put there, I do not want to heat it and in the winter the temp gets around 50 degrees, I do have some lake fish in it now such as a few perch, a couple crappie and just recently put in 3 comets, just put them in yesterday so am hoping they make it, would appreciate your comments, thanks bob