My new fish keep spitting the food out I'm giving them. It has been a few days of trying. At first they all spit it out. Now a couple of them will eat it. Do I keep trying with this food? How long would you keep trying? Will they actually eat it if they get hungry enough? This is their main food. It's Tetra Tropical Flakes. Once they get used to it, I plan on adding Bug Bites Tropical Formula, freeze dried blood worms, and veggies into their diet.