Off-hand, it does not look like your paper is clearing very well, but it could be a number of other factors in the image - it may or may not be part of what you are seeing. A question: how old is your FeOx? I have been told it is good for six months, but only keep my FeOx three or four weeks.
I do not prewet. I use sunlight and Pictorico and cannot relate to times with a UV box.