I COMPLETEY disagree that all tanks are prison cells. In fact, with the pollution in our oceans, especially in coastal areas, some of our tanks are the epitome of ideal. With the technology and know-how, we can create reefs that will grower faster and be more healthy than those in nature. Many small reef fish stay at the same reef over their entire lifespan. So I fail to see the difference. Especially with tank-bred fish.
Picos are controversial. Picos with multiple fish in them will get slammed all day long. You are lucky that most of the people at this site are tactful with their approach. On other sites I frequent, you would be criticized personally for putting multiple fish in that tank. Take away the substrate, LR, HOB filter, powerhead, heater and coral, and you have less than 1.75-2 gallons of water AT BEST. If half the fish die, and it is not caught overnight, it could be lights out for the entire mini-reef. What happens if you go away for 3 days and you have 1/2 gallon evaporate? What if you go away for 3 days and a fish dies? Most likely you killed everything.
It's unfair to post something this controversial and then say, "My girlfriend only wants nice things said about her tank." Because #1 she needs to understand why responsible reefers dont keep multiple fish in 2 gallons, and #2 she needs to understand why responsible reefers dont keep multiple fish in 2 gallons. I repeated this because there is HUGE downside to what you are doing, and you better prepare her for the reality of the situation, especially if she is ALREADY so sensitive about her reef. She must love it, which means she is going to be very upset if she loses it overnight.
The more of the cons she knows, the better she will be able to prevent potential problems.