i want to hang a shelf to hold my detergent, fab softner, etc above my
washer dryer combo in the basement of my house.

That stuff is HEAVY, be sure to use good supports and strong shelving
material. As in, not just some flimsy brackets spread 5 feet apart and
particle board. Use wood for the shelves, not just MDF. Then make sure you
space the brackets within 3 feet of each other, if not a bit closer.

I say this as the former homeowner put up crappy shelving with flimsy
brackets, too far apart, and that 20 gallon bottle of Tide sealed it's fate.