White poop can be indicitive of an internal infection. I don't have my book at home, but if you can get your hands on a book called, The Handbook of Fish Diseases, by Dieter Untergasser, that will help, unless someone else comes along and can give specific meds.
I would also work on PWCs to get the water parameters as good as possible as stated above.
Age is relative, you are only as old as you act....of course, this works in reverse....
the tank was one month old when i put the fish in.
Length of time is no indication of whether or not a tank has completed it's nitrogen cycle. The only test is to test the water and get the 0 readings and then check again to be sure it's stable and not just a dip.