Well I actually use a white 5g water jug, not a real ato container. I drilled a small hole in the screw on lid and put the water line through it -- I have that anti-syphon valve just under that lid. I put it there so I could maximize the volume of the 'reservoir' but not get the hose leak back on the floor (water
will come out of the anti-syphon valve)
Because I got tired of the hose getting caked with Kalk I've switched up to using saturated kalk water at a 1:4 gallon ratio. Your hose will get caked with kalk, I suggest doing this