Originally Posted by periwinkle1239
I believe you need to take a reading with a hydrometer, not refractometer to get an accurate gravity because of the alcohol present. This is true for normal brews, so I would assume the same principal applies to starters. Refractometers are good for checking gravity while mashing or boiling. Hydrometers are for checking final gravity.
True. But to use a hydrometer might not work. Not enough liquid.
Just let the thing run 24 hours, cool, decant, step up with more new starter wort.