Re: Should my prewash be cold or hot?
Yes you will need to experiment. I have hard water and a front loader. For some reason a hot wash/rinse before my regular hot wash works best in my circumstances. I follow this with a cold rinse. It's keeps the stink away and I am happy to have found a solution that works for me.
I think general across the board recommendation is cold rinse/hot wash/cold rinse.
Mom to two wonderful kids 10 years apart and my wonderful husband of 22 years.