I guess it was letting them go longer and higher water temp. Last time after 7 days they looked the same as when I cut them but had no nubs or root or anything so I threw them all away. I had been reading that most get nubs in a few days. When I failed I started with 70F water, that time I started with 82F. I now use a small aquarium heater to keep 82F. Shit is easy once you do it.