As for hardy "beginner's" anthias, I've had great success with P. bicolor many times mostly solo. They adapted easier than other species and ate almost everything I fed. Even solo though, I've kept them in tanks as small as 55g with a couple other fish, but would definitely recommend at least a 75g because their max size is towards the high end of anthias at about 5". The P. bicolor's seemed to put up with more aggression than other species too, even from a nasty clarkii clownfish.
Besides P. bicolor, I've experienced P. squamipinnis, aka lyretail anthias and P. bartlettorum or bartlett's anthias are good choices I would say for someone beginning to familiarize oneself with caring for anthias.