Hey. I have an auto going now, older than yours, and I remember around the one month mark I had trouble telling gender too, and I wasn't completely sure until almost a week after, but they say it takes longer for females to show sex, so it made sense, and the seeds I ordered were feminized, but make no mistake, Not all auto seeds are feminized, so unless it said so on the package, there is a chance there's a male in there. Oh and it's also worth mentioning that comparing mine at one month to mine now, she has literally tripled in size, and she's a Lowryder #1, up to 20" now. Now if I read your post right, they are a month old, give or take? Chances are, due to the age and not showing sex just yet, they may all be female, and if something must die for the greater good you might have a tough choice to make. I know when I had to choose only one plant out of two, I chose to save the taller one, which ended up being male, but that was bagseed, with auto seeds it's hard to tell what traits it shares with non-auto breeds, so I don't know for sure if tallness is a possible indicator of maleness with auto's as well.