Like mojo said its absolutly posiible to develop an ick issue with dropping themp all of a sudden to much. The I always drop it by around 4-6 degrees and this could potentially cause an issue as far as anything stress related goes. But with a good healthy tank and good healthy fish, regular w/c routine we all know that a little stress will only rarely cause an issue. And realisticlly how do we all treat ick? Raise the temp so if for some reason the fish do develop ick (I have never had it happen because I always use healthy stock in an established tank) the "cure" to ick is just around the corner with the raising of the temp. And adding a little salt shouldn't mess up the breeding prep you have been setting up for if it was essential. Nice take on it though, never thought about that for some reason. Isent it strange how its allways the simple things that can be over looked sometimes?