Are you sure that yours are really Tapajos? People down here have been advertising that they have Real Tapajos for sale for years and I am yet to find any. Just about everything in Melbourne is Rio Araguaia and not Tapajos, no matter what they are being advertised as. I myself have bought three different spawns of Tapajos Guaranteed and grown them up to find that they are Araguaia. You can't tell the difference at an early age but as an adult they all show the horizontal line from the gill case to the lateral spot (Rio Araguaia).
If you know of a secret supply of the real stuff, I would LOVE to get some.
Yes mine are real topajos as I bought mine from a good eartheater breeder down here so i trust that they are topajos and they look the same as the topajos in books so i guess they are the real deal