glad to hear he's finally eating. it was more than likely a simple fact of him acting grumpy after being moved into a new tank. the older a fish is, the longer it seems to take for it to get adjusted to a new tank. my male trimac is ~10" and wouldn't eat for around 3 weeks when I moved him to a new tank. the older the fish is the moodier it is.
as for the temp, 80 should be fine in a general sense for CA cichlids, in fact when I find fish not eating I'll raise it up a little higher to around 84 or so. there are a few cichlids that won't handle the higher temps like that (Thorichthys are an excellent example) but most others will be fine. the raised temp will raise their metabolism usually getting them to start eating. once they start eating then you can slowly reduce the temp back to normal.
however, considering the tankmates you have in the 180, I'd actually lower it to say 72-74. as I said before, the higher the temp the higher their metabolism and while this will usually get them to start eating, it will also usually increase aggression. lower temps will lower metabolism and in some instances will also lower aggression. considering the midas and flowerhorn in there I'd keep the tank temp kinda on the low side. anything you can do to reduce aggression will help considering the aggressiveness of most FH's and RD's.
if you move just the male and female jag to a 75 keep a very close eye on them. a mated pair who grew up together from the juvenile stage would probably be ok for a while in a 75, but putting 2 adult cichlids like jags who are brand new to one another could cause trouble territory-wise. if the larger male doesn't take to the female, it wouldn't take long for him to kill her. just keep a very close eye on her and have a backup plan ready.
