I have been trying to get a large stable school in my system for about 6 months now;
The only issue (and its been a huge one) is that they ship very very poorly, so some come in not eating, and never start eating, and die.
I have 7 healthy eating threadfins, but have lost aprox. 20 to get here. (First batch of 10 from LiveAquaria all died in 2 weeks). Next, got a batch of 5 from LiveAquaria Diver's Den; all survived. Then, got a batch of 13 from LFS -- 11 died. Will hopefully be adding ~3-5 more in the next week or so.
So far they seem to deal with my flow (which is tons)... but I would not recommend strong flow for them until they start eating. Otherwise keep them in a calm setting.
How much is ORA charging for them? I'd love to see how theyre breeding them, cause the only other person I saw come close lost all of the babies after 45 days.