On your grass carp. If your grass carp are more than 3 years old you may want to look into removing them later and putting younger grass carp in now. Grass carp will eat up to 100% of their weight for the first couple of years. After they reach 10# they tend to drop eating to around 25% of their weight. Also note that as water temps decline the grass carp slow in their eating. This would mean it may be more productive to add some grass carp now and then remove some of the older ones nearer to summer when the water temps get higher.