I got a very basic question about M9 plate. Several months ago, I made a
batch of M9 plates which worked very well. This time, I made another
batch just following the same receipe and I got a kind of dark brown
liquid after autoclaving. Bacteria refused to grow on them. I remembe
the first time I prepared M9 and got a almost clear liquid. So I figured
I must have added something wrong and repeated once. the result was the
same. Could someone tell me what color should be the final M9 plate?