washing dishes-is grease and food safe down sink drain?

I would not put grease down the drain. Wipe it out and throw in garbage. As for food juices left on plates, I do rinse it off if there is only a little but make sure the drain catch is in. If it is not just a slight film of sauce, I wipe it off and throw in garbage. I try to prevent anything extra going in that tank! Have fun.