That makes two of us. Fluid seeks it's own level. I'm not sure how a second tank would solve the siphon problem. I could be wrong, but I don't think that is the reason the heli guys use it. At any rate, I have a Saito 1.00 inverted in a warbird, same problem. I just clamp the feed to the carb when filling the tank and remove it at the last second before starting the engine. My engine is well broken in and tuned so it starts on the first try. If it doesn't start immediately you have to be careful not to flood the engine.