LPG range extender tank

[wuckfitracing]

Does anyone know if it is possible to add an another tank to my existing system. The existing tank is under my car and I could,on longer trips put another in the boot. I know it could do it as a fixed tank as there is the room but ,are there any quick release pipe fittings that anyone has used before.
Planning towing my caravan to Sweden. Car is a Suzuki Grand Vitara.