How to culture up yeast from bottle conditioned beers

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That is way too many steps. The yeast biomass does not grow linearly like you are treating it. Yeast grows exponentially at a rate of 2^n, where n is the number of replication periods and the symbol "^" denotes raised to the power of. The step sequence is usually between 4 and 10 times the volume of the culture being propagated. For example, If we start with 50ml of boiled 5% w/v (1.020 S.G.) wort, which is 2.5 grams of DME dissolved into 50ml of water. The next step will be 200ml of 7.5% w/v (1.030 S.G.) wort, which 15 grams of DME dissolved into 200ml of water. That starter can be stepped to 1L of boiled 10% w/v, which is 100g of DME dissolved into 1L of water.
 
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