I've seen Altifrons at HOT several times, so I'd check back occasionally and they should show back up. If you want large fish (4"+) you're better off picking them up than having them shipped.
I went to see the arowana today.... It wasn't a 55g it was a 30long.. Fish was at bottom of tank. He swam around when he put food in and looked healthy .... Just very stressed. I transferred all of my fish that were left in the 125 into another tank (they will be picked up tonight) I removed all of the gravel because it had crushed coral in it. Ran down to Leslie's pool supplies and bought 100lbs of pf sand. Sand is in the tank and rescaled and filled. Tank is back up and running... Almost no clouding at all via the plate and bowl trick and I did not wash the sand at all... I didn't want to have to rush this transition but I felt bad for the arowana. I think that until this guy is settled in and doing better I will wait on tank mates. I pick him up early tomorrow morning.