Invader Xan
Fish Crazy
do they do better in groups?
Yes, much better. Actually, with the exception of long arm shrimp, all shrimp much prefer to be kept in groups. Certainly any kind of algae eating shrimp will be much more active and interesting to watch in a group. Just a single shrimp will spend most of it's time hiding.
My amanos almost behave like a tribe. If anything scares them (like me cleaning the filter), they all like to huddle together.