i have just purchased a 230 gallon tank that is two and half hours from where i live currently. i am going with a couple guys to pick it up tomorrow. i am building a metal stand which i will case in wood. i have also a small tank that i am going to use for wet dry filter sump. my friend is cutting glass to section it off seeing is he can get it at discounted price. i also have an old air tank with a regulator on it, i belive it is about a 10lb tank that i hope co2 will go into. my main concern is how long the co2 tank will last with my large tank. and any other suggestion, comment, idea, anything will be helpful. thanks