Hi MyQul, thanks for the guide. You've inspired me to try this out, and not being one to do things by half, I'm planning to propagate a Westmalle Dubbel for 20 litres of a 1.075 OG belgian. I'm assuming your instructions get us to about enough yeast for a mid-strength 20L brew, and that I might need about double this. So, would one extra step up with 2L of 1.04 wort be enough do you think?