[Seattle_Aquarist]

Hi Ericpop27,

When I used DIY CO2 I had similar problems. The problem was the fact that I used really warm water when mixing my solution and was connecting it to the aquarium right away. As the liquid cooled, it created a vacuum that allowed water to flow from the tank to the bottle and/or it caused the bottle to "compress". If you are using really warm water to mix up your solution, try waiting overnight, or until the solution is room temperature before connecting to tank.

 

[Seattle_Aquarist]

TimboJones is partly correct, both water volume and air volume are effected by temperature; both are subject to the laws of Physics.

YankyTexan, you are right, it is the water that causes the pipe to burst. Water volume contracts as it get colder until it reaches the freezing point. Water as a solid (frozen) takes up more volume than the same amount as a liquid.