According to Kodak " the agitation will form large volumes of persistent air bubbles." When I am done washing my film I manually agitate in Photo Flo (wearing rubber gloves to protect my skin). In the pass I had problems with scum buildup and tacky residue. I solved the problem by using Photographic Solutions "Multi-purpose Darkroom Cleaner" for cleaning my Jobo and Paterson reels. Helps to use a toothbrush.