I have one Lyretail Anthia,one of the easier anthias to keep for almost 2 years now.I also have Sunburst Anthia and it is doing great too.No fighting between those two.They don't need to be in group to do well.You do want to feed Anthias at least two times a day.If I was you with your tank size I would get a nice group (male +3-5 females) ,they look cool in groups.