Here are some more knowledgebase web links for roof cleaners you will find helpful.
This is technical site used by many companies for quick and accurate technical & chemical discovery info.
I think it should serve the Roof Cleaner well and should be on everyones SHORT LIST of where to go for answers to many conversion questions and chemical and material compatibility solutions.
ColeParmerChemical
Here is an online fluid/air conversion table to make fluid, hose friction loss, etc. much easier to understand