Rice hulls are a filtering aid that help improve the speed of lautering, and they also help to avoid a stuck mash. They are particularly effective when brewing high gravity beers with a large grain bill and beers made with a high percentage of speciality malts. Rice hulls are also helpful with wheat and rye beers, since those grains do not have husks. Rice hull usage should not exceed 10% of the grain bill.

Rice Hulls are a filtering aid that improve the speed of lautering. Rice Hulls are particularly effective when brewing high gravity beers with a big grist; beer made with high percentages of specialty malts; and wheat and rye beers
Add 2-5% directly to the mash before lautering.