Too much foam? Your shake flask is too vigorous or your bottle is too full. Fill no more than one-third of the container for liquid cultures. The headspace lets oxygen dissolve, which most E. coli appreciate.
Plates not setting? You forgot the agar, or your autoclave cycle was too short. Double-check your recipe. Agar needs full hydration and a complete melt at high temp.
Lb Agar Medium Recipe | Bryont Blog
Contamination showing up as weird colors or smells? Toss it. Your nose knows—if it smells like sour socks, it’s not LB anymore. Start fresh.
