get a divider, let them get used to each other first, if not, theyl kill each other. the flower pot is for the female to lay eggs. ive heard chingmax is good food for flowerhorns, grand sumo, market rep prawns are good too. i only have a female right now, and i feed her hikari bio gold +, since she really dont need any expensive flowerhorn feeds. u do have a heater right? if not, you really need one, since they are tropical fish and needs warm water. so far, i think your good to go, hence that you have the regular stuff like filters, lights, etc.
cheers