Our Maruta brand Rapeseed is manufactured in Japan by the suppliers to the Isei Shrine. Nearly impossible to overfeed, as it is long lasting -- replace every 50 days in Summer, 100 days in Winter. Each cake is approx. 1" diameter by 5/6" thick, and consists of Rapeseed Oil Cake and its powder. No bonemeal or any other animal ingredients. Apply cakes at the rate of 3-4: 5" container, 4-5: 6" container, 5-7" 7" container, 6-8: 8" container. Does not deteriorate even when it appears moldy.