I still have the bottle of Photo-Flo I bought in 1984--I use it for cleaning things that I don't want to use strong detergents on, and also as a wetting agent for my brush when I spot prints. But I NEVER use it on my film anymore. I had a plethora of problems with water spots that all disappeared when I switched to LFN. With LFN you only need 2 drops per liter of distilled water to make your film dry spot- free. The first little bottle of LFN I bought lasted almost 10 years. Now I'm on my second bottle.(posted 8494 days ago)