Preflop – Good.  I honestly don't think any other option is good here.  AJo is good enough to play in position against these guys, but probably not ahead of UTGs opening range.  You don't want the fish to fold pre-flop here, and even if you think he's calling your 3bet, I would much rather flop a pair before trying to put more money in the pot.

Flop – I think UTGs value range here is probably AJ+ and sets.  Maybe AT, A9s, but you said he's not too aggro, so I think you are behind his value hands.  Given the 3way pot and an A high board, I doubt he's just firing away with his whole range, I would expect him to check pocket pairs and whiffs.  He probably bets out with flush draws but with the Ac on the board, he may have as few as one combo (KcQc), maybe as much as KQ,KJ, QJ,JT,T9, but that is still only 5 combos versus at least 24 combos of AK and AQ, so I think you're probably not in great shape here.  I wouldn't necessarily fold as you have 3 J outs, running flush outs, plus some chance of bluffing him off top pair depending on how the hand plays out, but I really don't like raising.  I think I like folding best, calling 2nd best.  If you call you have just over a pot-sized bet left, so if you do choose to raise I would just shove if you think you can get him off AQ.  

Turn – this is basically a shove, and I really don't see why he would do this with anything you beat.  Fold.