Thanks, esearing. I keep Photoflo out of the tank, putting washed negs in a tray of it instead. My normal development is 9 minutes. I may try your long presoak; I have used a 1-minute one, which appeared to make no difference. Otherwise, I'll continue to experiment with agitation schemes. Tim, the 445 inventor, has been responsive and helpful as always; I'll just have to keep at it.