You can go from the ceramic 1600 directly to the Chosera 5K. I suggest making a little slurry on the 5K by wetting the stones, and rubbing them together. This will make the stones a little more aggressive in cleaning things up and establishing a true Chosera 5K edge.
Depending on your level of OCD, you may want to step back to the 3K Chosera to really clean things up before the 5K.