[spawner]

Cleaner shrimps are loosely pair bonded, they aren't really found in groups like peppermint shrimp are. You can take two shrimp and get a pair, normally you don’t have the problems with pair bonding like fire shrimp. They are found in aggregations, but if one where to observe the "group" it would be likely that they are a lot of pairs in the "group"

They will kill another cleaner shrimp, normally when it molts they chase it around until they can catch it and then kill it instead of mating with it. Interesting enough the third shrimp knows this and tries to run and hide. So depending on how large your tank it you most likely the pair killed the new shrimp. For example, if you put three small cleaner shrimp in a 20 gallon high, they normally are fine until one or both of them become hermaphrodites; then they will attempt to kill the third shrimp when it molts, normally the third shrimp will escape but you will notice that it has gotten a hair cut (antenna are trimmed) that is from the aggressive pair.

You can keep fire shrimp and peppermint shrimp with cleaner shrimp, but normally you will not keep three cleaner shrimp for an extended period of time unless you have a very large tank with a lot of flow and hiding places.