I germinate lots of seeds besides cannabis, and for overall multi-seed use, jiffy mix is very good....the jiffy pellets work very well for ganja, tithonia, tomatoes, zinnia, sunflowers etc. ....larger seeds seem to do better with the pellets. The major caveat in using pellets is that they can dry out very quickly as plant grows (esp. w/ HIDs or outdoors).Transplant quickly!
I like to use ProMix BX with about 50% added vermiculite...this helps a lot when trying to sprout tiny seeds...like coleus. Vermiculite retains moisture to assist with stubborn seeds as well.
I germinate cannabis seeds in paper towels or cheesecloth and put the little boogers in the soil as soon as little tip pops out upon splitting shell.
My impression is that cannabis seeds are not as finicky about the medium they are started in as many other types of seed. Straight ProMix works well as have all other “starter” soil mixes I’ve tried using for marijuana starting.