What CO2 kit did you buy? It should have come with some kind of diffuser that you place in the water and connect it to the cannister containing yeast, sugar and water, with a tube. You should see bubbles coming out of the tube.
ok thats good, ic bubbles comin out of plants. I am using the JBL 100, which is non pressurised. I have a 200 litre tank and the bottle is for 100 litres i think. Should i buy another one?? or is one ok?
What bit of CO2 kit is it? I've yet to find a decent non-pressurised kit that will product enough CO2 for a tank that is 200lt, without lots of hassle.