Hi all, I bought a dennerle CO2 bio-line (I think it's called) kit which is a bottle of sugar gel, a capsule of yeast, a 'Topper' (CO2 diffuser), bubble counter, insulated box and some tubing. So far, I'm not impressed. The gel is supposed to keep the CO2 production fairly constant and longer lasting than the normal mix. They claim a month. It took 3 days for my first bubbles to appear and the rate is about 1 bubble every minute. The CO2 collects in the 'Topper' which is just a box that water flows around and 'absorbs' the CO2. Anyway, the point of the post was I was wondering whether I could make up my own gel, bearing in mind the official bottles cost just over a fiver. I found some links on the net where people have done exactly that, but without any views on whether it worked or not. I then had a eureka moment. Could I make up a gelatine mixture and intead of adding the whole lot to the bottle, put it in an ice cube tray and add a couple of cubes every few days? Am I barking?