I didn't know much about any kind of plumbing. I don't think I was paying much attention in the fluid mechanics part of my physics class 50 years ago and haven't needed to use any of it until lately. I quickly learned that black pipe and it's fittings are cheaper than equivalent diameter hydraulic hose and fittings and they seem to be used pretty much interchangeably.
The farm supply had a rather limited selection of hydraulic components and I might have been better off having custom hose assemblies built by another company which does custom work but I opted for off-the-shelf stuff. It came in one foot length increments from 2' to 5'. There were male fitting on both ends.
I got free conflicting advice on whether 1/2" hydraulic hose or 3/4" hose would make a noticeable difference. As it turned out I had to use some of both because that's all the store had at the time. High pressure hose isn't needed on the return line from the control valve to the reservoir or the "suction" line from the reservoir to the pump, as I understand it, but I'm not keen on hose clamps. They look tacky and the high pressure hose seems to just dress everything up and make it look more expensive, which it is.