hi, i set up my diy co2 and followed a 'recipie'. however it is not producing any bubbles and not even any pressure in the bottle. i think it may be the old yeast, so i may have to get some new becuase sugar is new and so is the bi carb. anyone got any thoughts, tips, suggestions or shortcuts on diy co2? i really want to make it work! also when it is in the bottle should it be below the tank or above? i know it shouldnt make a difference because the gas will be pussed through but iwant to know how other people do it! thanks.