5. Feed it
Once your starter is active, you’ll need to feed it. Starters, in many ways, are like children. You need to feed them with enough fuel to sustain their growth. Add another quarter cup of water to the starter and stir it.
You’ll then add another half cup of whole grain flour and then stir until it blends in with the rest of the starter. Once again, you’re gonna need to wait for the starter to rise. You’ll often see a two-fold increase in size within the first 12 hours of feeding it. It could take up to 24 hours at times though so don’t panic if its growth isn’t as speedy as you’d like.
Sometimes the starter will bubble rather than expand but there’s nothing wrong with that either. Be sure to stick to the formula when feeding your starter. Getting impatient with its growth or overfeeding it can lead to disastrous results.