Whilst I do have a permanent darkroom I did have dust problems.The solution was a home made film dryer made from 3 large metal coffee cans,an old fan from a range hood & a foam filter glued to the inlet side of the fan. I can dry 3 films,on the reel,in about 30 mins with no dust or drying marks.I also stopped using photo flow or any wetting agent.I think you are on the right track in using tubes & a fan it is a similar idea to what I used & it works well.Try not using wetting agent;just give the film whilst still on the reel a good shake before completing the drying in your home made film dryer.(posted 8201 days ago)