I agrees with digiman's opinion, but with a food dosing system, it seems like they can sustain quite well..
- Pseudanthias smithvansi (Tried it, even in a tank without any tankmates, they refuse to eat and come out of the caves)
- Pseudanthias flavoguttatus (Too rare and too ex for me to try, rumour is they are very aggressive if you managed to keep them alive)
- Pseudanthias tuka (Relatively to feed, but they will MIA for no reason)
- Pseudanthias bartlettorum (Easy but too common)
- Pseudanthias evansi (Never keep before, cant see the difference between Tuka and Evansi)
- Pseudanthias aurulentus (Too rare in Singapore, it is rare even in the States)
- Pseudanthias ventralis (Too ex for me to try and heard a lot of problem with them)