Hi Deborah, when Graeme did his workshop here we made up an IBC (1000l) with the following:

50 litres of Molasses is required

100 litres of BAM (Beneficial Anaerobic Microbes) is needed.

Water to fill the tank (but leave some room at the top for expansion

So for a 200L version just 20l BAM & 10l of molasses

Also important to install a release valve: Drill a hole in the top of the IBC, cut approx 1.5 meters of garden hose, insert one end into the IBC and the other into a 2 litre bottle filled with water outside the IBC. Use a zip tie to attach the bottle to the tank frame.