titan97

Alright people, I have a query for you all. I just set up my DIY CO2 last week. After 2 bad batches I learned how to get the damn yeasty-beasties gassing. Now I get about 1 bubble per 3 seconds (20/minute). NO problem, right? Well, I use a DIY bell diffuser (tupperware-style) that catches the bubbles and holds them in contact with the water for a longer duration. I know it is not the most sophistacated solution, but I did say this was a DIY setup, right? Anyway, I did my first water change since installing the CO2 today and I figured I should try to move the bell lower in the tank before I remove the water and free up all that lovely CO2. This way it will still be submerged when I remove the water. However, when I moved the bell deeper, the bubbles stopped. I could see the gas/water interface in the tubing and it was not moving at all. So I did my water change and once the water level got low enough, the bubbles started up again. I filled my tank and the bubbles stopped. So I moved the bell up higher (and closer to the output of my powerfilter). Once again, the bubbles started flowing.
My question is this: has anybody elsebody else seen this problem? Is it normal to only be allowed 2 inches of head before the CO2 stops? Short of going to a pressurized system, is there any way I can increase the depth I can mount the bell?

Thanks

-Dustin