don't know about that claim, I am sticking with it trying to figure out hatching issues at my altitude and have had a lot of heartache usually after lock down but still am tweeking things to find what works best here, If it hadn't been for all the great people and ideas and support here from, Sally, chickencanoe,pd-riverman and so many othere I'd have given up long time agoDo it!I've only hatched one duck so far, but I think they're even more addictive than hatching chicks.![]()