my experience with gbr's and red cherries went something like this. got the shrimp. turned out the lights. added food to the one side of tank. added the cherry shrimp to the other side. the minute they hit the water my gbr's came over and started to eat them. one by one. i paid $39.99 for a 5 minute snack for the gbr's. never again. the shrimp are too small when you first get them. i would grow them out in another aquarium and then introduce to the gbrs. but i don't know if that would work either. when i put ghost shrimp in the tank that are full grown they ignore them. it might also be because the ghost shrimp aren't as brightly colored. the cherry shrimp just seem to scream here i am, eat me! in a nice way. lol