Ed, if you have a vertical forge it must be blown, you have nothing to lay the metal on while it is heating so you probably have to hold it with tongs or have a piece long enough to hold the area not being heated, if you are using flux the excess flux falls to the bottom of the forge and therefore out of the way and not damaging the floor of the floor. Your metal does not lie on the excess flux. Simpler to build.
If you have a horizontal forge you can have a naturally aspirated (non blown) forge, therefore no requirement of power. Kast-0-Lite is resistant to flux. If you have flux pooling on the floor you are using to much flux. If you build a Ribbon Burner you can do welds without flux. You can put the steel to be heated (even small pieces) into the forge without having to hold it. I prop my metal up off the floor so that the heat can circulate around it to get a more even heat.
I personally prefer a horizontal forge with a Ribbon Burner.
Let me know if I can help you.