saab griffin coolent and steering fluid enquiry

hi, I am new to this forum having recently taken ownership of a saab griffin.I am also new to saabs so can anyone tell me what type of fluid to use for the power steering. Also not even sure about the radiator coolent as the handbook states to use only saab coolent in a 50/50 mix. Is this critical? are there other alternatives? With previous lesser cars I would have just used water with occasional anti-freeze but I am worried about corrosion as the water is very hard chalky stuff where i live .Any advice would be welcome

i put 50/50 in my saab and it runs fine.. Powersteering I use anything and don't seem to have any problems, and i also put high octane gas

hmmmm, aquafina maybe. just throwing it out there. the only other thing that will work is supermans blood. good luck getting that