I am going to turn a cheap 70 litre rubbish bin into something I can clone in( maybe 4 at a time) I'll be using CFLs, not sure how many yet but I have some splitters. Question is would passive airflow be enough with some holes drilled at the top and bottom or would I need a small fan in the bin. Will be putting cuttings into jiffy's and then soil. Also is 24hr light better or 18/6. I could also add a small usb humidifier.