rcamigo,
You may be a bit hotter down in your neck of the woods than we are here in Oklahoma, USA. But not by much. You shouldn't have any troubles with the heat and the tank that came with the plane. As far as vibration, you should wrap the tank in foam to pad it against the vibration from the airframe. One source of padding that I have found that works great with tanks are computer mouse pads. They give enough padding to keep the vibrations down, but they are thin enough to fit into tight and cramped fuselages.

Hope this helps

Ken