So all I have to do is to get another charge controller and run separate wires to the battery.
Or use a diode.
I really want to see just where this diode is. Since you said it was getting warm, sounds like it is in series with one of the lines and not just the meter. If so, you just blocked charging. If not, it was not needed in the first place like people have been telling you.The diode works perfectly. It does get a bit warm, with a 4A load,