Hero (MP): Mid-20s, TAG but sometimes not aggressive enough. $220
HJ: Mid-20s, some sort of short-stack set-mine fanatic which I have trouble understanding. Has lost a big hand and is left with 15bb. I have previously folded ATo as HJ PFR 7bb (2 limpers before me) against his 3-bet all-in with 35bb, he showed 55. I'd so love to know whether my fold was correct - I consider it to be marginal. $30
SB: Early-50s, tight and seems relatively competent in hand reading. $600

Preflop

Hero, after 2 limpers decides to raise to $14.
HJ shoves all-in with $30.
SB and Hero calls.

Flop ($96)
8 5 3
SB donks $25, hero calls.

Turn ($146)
K
SB checks, hero has $165 behind and decides to?

I would have considered a preflop shove to iso the shortie with AJ off. SB range isnt that strong either after just calling the 30, so i guess it consists of alot of medium pairs like 77-1010,KQ,A10 suited and those kind of hands. AJ off doesent play very well in a dry sidepot and with a bloated preflop pot.

As played i would just check back the turn, realize my A high equity and give myself a chance to hit a J or A on the river.

Any read on what SB has in this situation? Will SB put AK in your range when you call flop? You can't represent much after you flat call preflop and flop. However SB's donk into a dry side pot has put enough money into play even if you don't beat HJ, bluffing turn may be workable. Checking to see if you can catch is also fine if you don't think a bluff is going to work.

Mostly though you should just be folding to SB's donk on the flop. He can't really be bluffing because he still has to beat HJ.

Pretty standard fold on the flop.

What happened:

Hero bets $55 (1/3 PSB), SB tanks for a minute and folds.
An A came on the river and hero scoops the pot, HJ did not show.
SB says good bet (not sure if mocking or genuine), and reveals verbally that he had a drawing hand.

I did not have any V specific read but I reckon the probe donk, in addition to his call weak. I agree mostly with the range Petrucci suggested but added a few drawing hands - and I believe his weak bet calls for it.

For this reason, I believe a bet would make him fold a large part of his range and decided to make the bluff. Betting $55 would still allow him to call profittably, if he had a drawing hand so I am not sure if it was the right decision.

I find folding flop too weak (what are we continuing with?). I am also not fond of the idea of checking back to rely on 6 outs (and potentially only 4 clean outs) - I find it very dangerous. I hope it's not me being too fishy and please do correct me as you please!

Your villain in this hand played completely counter to your assessment of "tight", if he had a drawing hand on this board odds are he flatted the threebet pre with a bad hand. Then he also led flop with a draw in a dry side pot. Maybe these things are aberrations for him but when you say "tight" I am expecting villain taking this line to show up with an overpair or better usually. If villain is capable of this sort of nonsense then you should just 4bet pre.