Not necessarily. Ive heard tons of stories with axies, guppies/mosquitofish/mollies/platties, and cherry/ghost shrimp living together for quite along time if the axies are fed extremely well. I hear that cherry shrimp seem to do better for some reason though and theyre really prolific, so if the axie doesnt go and eat all of them straight away, they can sometimes establish quite large colonies with them. Ghost shrimp have been proven really hard to keep alive in captivity and are hard to get to breed. They are usually looked at as food, so not handled too well and are usually damaged when you get them. Cherries are usually bred intentionally to keep as pets, so they are brought up well and are usually healthy. Just expect to lose some. I will be keeping a breeder tank of cherry shrimp and put some in the 55gal and see how it goes. If they live, I will put more in. If not, I will put some in when the breeder tank does its job and they hatch out more babies than it can hold. Its a personal choice, a game of chance really.
Mark