We have a 29 gallon tank with 5 fish, we recently had one if our female Molly's die randomly over night with out any sign of disease... Now our male Molly is somewhat wobbling around and swims with his tail down, head up...his colors have also changed a bit. He went from pure white with vibrant yellow and blue tint to a white with black tint, he is very lathargic and just moseys around aimlessly. He used to swim around and raise his sail fin to the ladies and act like hes the coolest thing since sliced bread but as of today hes just down in the dumps and we're really worried about him. I really want to help him out but I really don't know what is wrong with him or where to even start! So any help would be much appreciated. Also none of the other fish in the tank are sick they all are very active and happy.