and I just found this on WWM (sorry for blowing up the boards)
I am in agreement with Michael (1991) in not suggesting the necessity of group purchase and husbandry. The various Anthiines live in large aggregations with a definite pecking order that is not replicable or desirable in captive care. If you want to buy a colorful male, only buy one. Similarly, unless you have a very large tank, more than one (or two) females is unnecessary and may well lead to endless fighting and loss. If you lose your only or alpha (dominant) male, the next most dominant specimen will in time change sex to take it's place.
House only one species to a system. If at all possible, acquire all individuals at the same time from the same batch. I have seen all species offered in the trade maintained solitarily for extended periods of time. Solitude is not deadly to them.