Water Float Valve, Water Level Control Water Tank Traditional Float Valve Upgrade 2 PCS(1/2" to 1/4", side inlet)

why can't you send me the correct product? I've tried twice and keep getting the top inlet valve when I'm ordering the side inlet valve.

Can this be used in salt water (e.g. for a salt water aquarium) without corroding/rusting?

Will the 3/4" inlet unit accept a 5/8" garden hose connection? Or would I have to buy an adapter?

I want to use this for a fountain with a hook up to a standard garden hose. I have bought like 5 adapters at this point. Can someone direct me?