I can appreciate your enthusiasm...they are pretty. They are also prone to stress related issue such as ich.I have also read that they are susceptible to lateral line disease too. Quite often, you cannot get them to eat. IMO
it is better to get larger ones as the small ones do not do as well, therefore they can be costly.
But, here are the requirements as per liveaquaria.com
Minimum Tank Size: 70 gallons
Care Level: Moderate
Tank Conditions: 72-78°F; sg
1.020-1.025; pH 8.1-8.4
Max. Size In Aquarium: Up to 1'
Reef Compatible: Yes