Photoflo 200 dilution is 1+200, that's 5 ml per liter or 19 ml per gallon (US), there are (were?) stronger concentrates available at one time. We used Photoflo 600 at the college lab and I understand that there was a Photoflo 1000 available for photofinishing and cine processing operations. Don't use any kind of mechanical squeegee, sooner or later, probably sooner, you will scratch the heck out of your film. I use two fingers, first dipped in the Photoflo and then run down the film once. One of the reasons I prefer shorter 35mm films is that my arm span is not quite 36 exposures long and I used to have to cut 220 rolls in half after processing so that I could squeegee the film. Reusing Photoflo is false economy, things, horrible stinky things, grow in used Photoflo (unless you add some formalin). I am going to try a centrifuge (salad spinner) to get the last rinse water off my films, some folks say it works very well.
