$2/$4 No Limit Holdem
6 players
Converted at weaktight.com

Stacks:
UTG scarecrow2020 ($400.00)
UTG+1 pamz123 ($266.20)
CO Kjell_morten ($509.40)
BTN Dreddo ($942.60)
SB Hero ($647.50)
BB Playboy 8 ($400.00)

Pre-flop: ($6, 6 players) Hero is SB
3 folds, Dreddo raises to $12, Hero calls $10, 1 fold

Flop: ($28, 2 players)
Hero checks, Dreddo checks

Turn: ($28, 2 players)
Hero bets $20, Dreddo calls $20

River: ($68, 2 players)
Hero checks, Dreddo bets $50, Hero raises to $204, Dreddo ...........


Villan is a bit of a NIT on my small sample size, hes 12/12/3 over 40 hands, havn't seen much from him at all.
Do people think this is a good spot for a river bluff?
I felt the fact that he was really tight makes it better, hes certainly doesn't look like some curious TAG.

What about my bet size?
I am trying to rep a 4x or set, am I though?

My image at the table would be good, I am 21/15/1.6 and I have won any hands that went to showdown on the 30 I have played at this table.

The biggest problem here is that I think you have plenty of showdown value. His river bet is either a queen, trip fours, some wierd monster or a bluff. We beat his bluffs, and I'm not sure we can get him off much of his value betting range. I think if you truly believe he's weak enough to fold here often then he's also weak enough for you to just call.

You really should have just cbet the flop. This just looks super ridiculous weird, and villains most likely holding is Qx (which isn't folding).

Your line looks kind of weird, and there aren't a ton of monsters you could have here, so I don't think he's going to fold the ~2/3rds of the time you need him to (I think he usually has a queen here).