I've not had too much of a problem switching from live to f/t. I've purchased several adults feeding live and been able to switch them all to f/t. Sometimes it does take the animals longer to switch some are eating machines and have no problem switching immediately. What I would do is only thaw a couple at a time and offer to the pickiest eaters first. Then give it to another if they won't take it. Eventually they will get hungry enough to take it. Keep an eye on the animals body condition and if it looks like it's getting bad maybe search around for a live feeder. I know I've heard that it's hard to switch but in my experience eventually all of them did it. Good luck.