How long do you reckon the 500g co2 will last gf or do you have any idea, and do you think it would be easy to get such a small bottle refilled easily, or do you have to send them off somewhere and get a replacement and do without co2 in the meantime, this is why im leaning towards a regular co2 cylinder, you can just nip out and get it refilled somewhere locally and set it up again within an hour or so, i believe leaves on some plants grow smaller when you go pressurised, seems interesting.