Thank you WPStrassburg.
Size would be around 15 gallons. I know they are basically a cylinder and cone.
I'm more interested in optimal cone angle and cone height to radius ratio or cylinder height to radius ratio (for cleaning and better fermentation). What about size of a spigot (or maybe a valve) on the bottom? If there are two spigots, where should I put the upper one?
Is conical fermenter suitable for carbonation or it should be reinforced?
Sorry for my bad English.