While RedTails are an exceptional fish when you consider how not only long they get but how wide I don't think they're exceptional enough that a SB RedTail(assuming they max out at 20 inches) warrants a tank that's big enough for more than one 4 foot Silver Aro. So while bigger is always better it's totally unnecessary in this situation for the RedTails well being or comfort. Let's trust UnstoppableJayD since he's an experienced aquarists to chose the appropriately sized housing of his fish and leave the talk of bigger tanks alone for the remainder of the thread.
Since I have no way of knowing for sure I can only assume certain things that maybe affecting the little guys appetite. If he was transported from overseas specifically from where I think he has, he's just endured a seriously long and arduous trip. I'm also assuming that you either imported him yourself or had someone else do it and probably picked him up as soon as you possibly could upon his arrival. Since I've been keeping Flowerhorns, more specifically getting them imported I've had experience with fish that suffer from a long trip. With that said it's not uncommon for them to take longer to feel comfortable and eat. The only thing besides patience that I would employ is a watchful eye of his waste/stool to make sure he isn't suffering from any parasite problems due to the stress.
Anyway very nice pick-up, I personally can't wait for him to put on some size and for us to get updates. Good luck with your new addition.
