How to remove beer stone You will need an acid cleaner to remove beer stone. We suggest using something like concentrated Starsan solution or an acid cleaner safe for brewing equipment. Related articles Guide to Lagering with the GF30 & GC4 What is the coldest temperature the Grainfather Conical Fermenter can reach? Instructions - Conical Fermenter Pressure Transfer Why is there a temperature difference between the Tilt Hydrometer and the GF30? Instructions - GCAST