Dauer induction via cholesterol deprivation

Hi,

I’m trying to induce dauer in N2 worms using cholesterol deprivation. All of the literature I’ve seen says to make NGM plates with agarose in place of the agar, and to leave out the peptone and the cholesterol. Most protocols also suggest washing the OP50 a few times with M9. I tried all of this, but none of my worms went into dauer. Does anyone have any suggestions, or any protocols that they know work?

Thank you!