Low profile reservoirs for height limited rooms?

I would like to try the aeroflo aeroponics system or something similar, except height is an issue. This would be an attic grow the tallest portion of the ceiling is 72" and goes down to 32" over 82"s. These aeroponic systems use tall reservoirs between 18"-22". Are there any high volume containers that are short, but make up for it with surface area? An example would be Koplin ATV products makes a 4gal fuel tank that is only 3" wide. I was thinking of getting 4" abs piping and creating a reservoir by coiling it together and at the end use a 90* bend with a pipe sticking up and dropping the pump into that. There must be something easier. Any advice?

At places like tractor supply and agri supply they have a 50 gal horse trough 12" tall around 60 bucks us.

put a 55 gal barrel with one of them screw on or clamp tops. then u can lay it sidewise and drill a hole on the side as the top. altho that still might be too tall for u