EM and EM-1 are basically the same thing but some companies use different combinations of ingredients. They all just "Effective Microorganisms" In the article:
EM (Effective Microorganisms) and EM-1 contain yeast, photosynthetic bacteria, and lactic acid bacteria
So whatever company you buy from just watch the ingredient list and make sure it has what you want (you don't "need" the extra bacteria but its up to you). I've seen some "EM" mixtures that have lots of other good stuff and I think EM-1 is an actual trademarkd combination. In Asia they have different types depending on what you wan the microorganisms to do; 4 types of EM (EM1, EM2, EM3 and EM4). So if you are buying "EM-1" you are buying that specific combination of three bacteria (yeast, photosynthetic bacteria, and lactic acid bacteria). EM is generic microorganisms and could be who knows what (probably way more types of microorganisms/bacteria) so just read labels. The molasses is good to have for all mixtures as it is food for the microorganisms.
