I ordered some tabs from SCIdmt not to long, I've ordered from him a few time now. (He's my go to for LSD) Anyway, his listings are for 150ug. The previous times I ordered from him they definitely have been 150. They blew my mind! But now this batch doesn't seem as potent.. It takes more like 1.5 tabs to really get going. Anyone else notice this?
From your math, it seems they might be 100 ug.. Contact him and ask him what's up.