Villain is a middle aged player, fairly tight and aggro, has major postflop leaks like calling down TPNK or MP, opening JTo UTG 8 handed etc typical fish stuff.
Hero is viewed as very tight, pretty aggro TAG. Young internet player obv

2/5 NL
Hero: $800
Villain: $1500

Hero opens in MP+1 with AA to $25
Villain calls in HJ
All others fold

Pot: $55
Flop: 765
Hero bets $40
Villain shrugs and calls

Pot: $135
Turn: 7
Hero thinks for about 15 seconds about betting and checks
Villain bets $110
Hero tanks for about 25 seconds and calls

Pot: $350
River: 6
Hero instachecks
Villain bets $205
Hero calls

I'll post my reasoning if there's any interest, is this good/bad?

The call is fine, especially after instachecking (given the money in the pot and the flush/straight draw possibilities). However, I wouldn't recommend instachecking here without a 7 (unless u like tough decisions). Instacheck tells opponent that you are scared he has a 6.

Honestly, this is probably exactly how I play the hand several months ago. After reading on here, I have incorporated more raise/folding into my game.

Ranging V on the flop, I would put him on an overpair, top pair or middle pair, flush draw or straight draw. You opened utg, so I think any of these hands will just flat. I think a pair draw combo would reraise on the flop. Since AA is still ahead of a most of his range, I'm not check/folding the turn. The question then becomes, is it better to bet/fold or check/call. I think it is actually better to bet/fold. You can bet a little smaller, thus controlling the pot size, also if he has a 7, he will likely reraise you, because of the wet board, and you can cut your losses. If I thought this V might reraise me with a weaker hand, then I would stick with check/call. It's hard to say from your description of V. You say he is fairly TAG, but then describe the leaks of a loose passive fish. I'm going to assume loose passive and go with raise/fold the turn and river.

Fairly tight doesn't = opening JTo UTG or getting into pots with hands that make TPNK. Aggro doesn't do a lot of calling down with TPNK or MP he is raising those hands quite often. Your villain sounds more like a passive calling station.

I'd bet fold vs that player since most of his mistakes are going to be from calling. So I'd bet the turn and if he raises you'll be right more often than not folding. I also would have started pot controlling on the flop and bet it smaller in the $25 - $30 range, then your pot would be around $105 and you could bet $45 - $50 on the turn and adjust from there, fold if raised or bet/fold, check/call river.

I'm not a big fan of building a big pot OOP with single pairs, let alone on a board that crushes a lot of his calling range. I'm not looking to fold but I'm much happier in a pot that isn't bloated. I think the best way to do so is to be the ones making the bets at least until the river.

Against a calling station I bet big on flop and continue to bet big on turn on this very wet board where he can have plenty of draws and worse made hands he isn't folding anyway. Checking turn is a mistake, you are losing lot of value and at the same time give up the initiative and allow him to get a free card.

I think your beat on the turn TBH but you cant fold, and i think it would really require you to have a read on the villain to call the riverbet, is he bluffy because your only being a bluff