Thanks for an answer, I'll certainly try horizontal drying it's very logical. I never had problem with my workflow with 35mm film, and i did many rolls with tap water, i switched to demi because EFKE(ADOX) 25 is a magnet for crud from water, i don't know, maybe 10 times more than other films. I'm new to a 120 format, friend gifted me a Pentacon Six and i really enjoy in it. As for a fix time, Fomafix (rapid fixer) instruction says 3 minutes in 1+5 solution for film.