Hi,

I prepare NGM plates for C. elegans maintenance for almost 3 years now, and recently, even though I changed nothing in my preparation steps, some crytals started to form when I add the cholesterol (5 mg per mL of EtOH). Anyone else had this problem?

I keep cholesterol solution in +4 °C, I cool down NGM to ~55°C before adding the cholesterol. I add the cholesterol as the final ingredient all the time, and a crystal cloud form as soon as I add it. When I try to dissolve it by swirling, the crystals (they are usually the size of L3 worms) do not dissapear. I fear that this may be altering for the worms' lifespan, so I really need suggestions.

Thank you all!