Shrimps will eat anything. Best advice i can give you is dont over feed. Feed them twice a week if you have less than 50 of them, 3 times a week if you have more than that. If there is no fish in the tank, all the extra food will cause a bloom in other critters, like seed shrimp, little worms, daphina.
Cherries are super hardy, they like cooler temperature, but can live in temps up to 80, but they breed best in around 70. So no need for the heater. They do like to have live plants, because they love picking biofilm off them. thats what the baby shrimps mostly eat in the first few days of being alive, so you must has some live plants in the tank.
Any fish that can fit a shrimplet in their mouth will eat it. Unless your tank is super dense, dont keep any fish over 1 inches with them. Tetras, guppies, will all eat your baby shrimps, and will even eat adult shrimps when the fish is full grown.