The system can be converted to propane, but most people go the other way .(convert to CNG) The biggest reason given to convert is safety.. propane is heavier than air and will collect in the low points of your boat (like the bilge)..Cng will disperse in the air brcause it is lighter than air.. They now have CNG fleets like cabs,buses and police cars. It should be easy to get filled and is fairly cheap.. you could call you gas company, they now have pumps to fill your car at home and billed through your gas meter at the house. I would keep what you have.. but if you do convert let me know what you want for your CNG tank and accessories.Mike WD9EOUC-38 s/v Chute the BreezeMichigan City, INmosilver@netnitco.net