Was wondering if any one can advise on one of these things, do they work?? Carbon Dioxide Supply without Gas Bottles The Zac Carbo Plus consists of an electronic controller which is fitted outside of the aquarium, and a Stainless Steel and Carbon Sandwich which sits in the water. And also went o lfs today to buy a c02 kit, didnt have any jbl, can anyone rate the following never bought cos i wasnt sure! 1 Ferplast 2 Hydor green nr6 3 Aqua medic 4 red sea Also do any of the tablet form co2 systems work? Thank you.