Hi All Ok, so I went through all/most the threads regarding CO2, which mainly were about the Cylinders, rather than the complete setup. (I need one) I think it would be nice to have a place where people can specify their rigs, and if they would recommend them, or not. ps. On my WWW travels, I found this: http://www.aquariumplants.com/CarbonDoser_Electronic_Co2_Regulator_p/co2.htm If someone knows of a small enough valve / solenoid, I can get one of my friends to build something similar. PPS. Transfire charges R850 for a 5kg Fe, Filled, with the Gate Valve, fitted. Should you be interested.