rubber roof cleaning

I cleaned our trailer roof with "Dicor Rubber Roof Cleaner", today. I used it because I had it and felt it was something that wouldn't damage the rubber. I guess, I would like it to be cleaner and I would like to use a product other than that sold by the manufacturers for convenience more than cheapness, but feel simple products work better. I have tried the Murphy's Oil soap and not impressed with the results. I'd like to try the Spic and Span, but unclear if this is a liquid soap or the powder my Grandmother used. Doing a search here on cleaning roofs, pone person said he had used Spic and Span for ten years, that's the kind of product I'm looking for. So is the Spic and Span liquid or powder? Thank you for your time.