Live 5-5 plo, stacks are between 2k and 6k...table is full of passive and straightforward fish...fish straddles button for 10, Tilting fish in SB 30, two other fish call, I make it 110 on cutoff with AhJhAx9x, everyone calls. 6 to the flop of 965hh. Checked to Fish in front of me (hijack) and he pots it for 675, he started with 3.5k, he is also super stationy and always has the nuts here. I cover everyone, and stacks behind me are between 3-6k. I'm next to act, how should I proceed?
Also, take into consideration that every player runs it twice when all in.

"He always has the nuts here.". I dunno if I'd ever fold here with position. He might check some turns giving you a free river so I'd call and he might even have a set so an ace could be great for us too. And running it twice doesn't deny the fact that you'd be getting it in behind vs the nuts.

Call

Well if they're running it twice then it makes sense to just gambol

fold, can only call here if they run it atleast 3 times

call then bluff a 5 on the turn and get stacked

Not sure what I'd do here, but I prefer a flat pre flop as when hands go so multi-way like this, you'll find that even with loose fish at the table that there are a few high cards out in people's hands, including 1 or perhaps both of the remaining Aces.

This is not just a theory by me, it is based on playing a lot of hands where exactly this happens, a raise pre, a 3 bet and lots of callers. Amazing how many times the flop then comes as 3 low to middling cards.

And anyway your edge in this game is primarily post flop and everyone is sitting deep, so unless you feel you can isolate one opponent heads up with a superior holding to theirs, I feel that playing solid starting hands (widening your range out a little more than usual) but not inflating the pot too much pre flop is the right strategy against fish sitting deep.

The more you inflate pots pre with them when it is multiway, the more you are giving the fish a chance to beat you through variance, rather than through skill.

Raise PF is fine. I'm never folding on this flop and certainly not raising since it's multiway. Agree with SageDonkey on all fronts. No need to inflate pots when we're this deep stacked. It's possible the hijack has AAxx too, and is overplaying his hand. Even if he luck boxed the nut straight you still have outs. Call, re-evaluate on turn. If we don't spike a heart on the turn, any weak-ish bet should be called.

AC

I can't see doing anything but calling.

pre is obviously just a 3b your gonna be fine as long as you do this w a strong balanced range w some diff board coverage
this is one of the nutty worst boards tho i think u can cf or cc
vs pot here your implied odds arent so good and obv your immediate odds suck

I think its closer to a fold then a call with the potential for additional action behind us and uncertainty about the number of outs.. we are deep enough that making a conservative laydown is quite reasonable unless we want to invest a lot drawing

Grunch: Fold. One pair with the NFD for stacks is a death sentence with four pkayers behind. What happens when you get raised behind? What do you do when everyone folds (fat chance, bub), you turn an A or air and he pots again?

As for the general question on how to beat fish? Coolers, setups, freerolls, domination and patience.

Pot pre for gods sake. As played I think it's a fold not a call. If the fish will gii for the rest on brick hearts then maybe it's worth it, if not, it's a fold especially if you think he has nuts 100%