RIVER DECISION: TO BET OR CHECK?

i think it's the worst option to play this hand.

1. always play with 100 BB
2. on the flop you should bet because you can get money from weaker hands like 99-TT, the last K (maybe JJ then you are tight and he doesnt want to 3-bet) and there is also a flush draw
3. why do you check raise de turn? weaker hands with one pair will fold for sure and lower sets would have bettet the flop.
i think he called here a FD, so you have to check back the river and get less value then you play bet bet bet

I agree with the above.
Stack, betting ...
As played river is xb.

You should be playing with 100bb stack.
OTF I would just bet. It is a good plan to just play straight forward at the micros. I see no reason to check here and by doing so we give free cards to draws.
As played I see no reason to check raise turn when it is a blank.
I think villain won't call your xr with any other hands than strong draws which got there OTR so you have to check behind.

You should not be playing NL25 unless you really can afford to lose. Basics of poker is that you bet your good hands and do not bet your bad hands. Later, with some routine you might mix it up a little bit and check good hands 5% of the time or so, and bet your bad hands 5% of the time, and so on. Before you know when to mix it up, and how much, - don't do it.

Yup, 100bb stack. We bet flop for value. We xb river.

As played...

River: ($11.85) A♦: (2 players)
SB checks, Hero bets $6.25, SB calls $6.25

Results: $24.35 pot ($1.21 rake)
Final Board: 8♦: 2♣: K♦: 3♥: A♦:
SB mucked and lost (-$12.05 net)
Hero mucked K♣: K♠: and won $23.14 ($11.09 net)

I knew in the moment that I had played the hand badly, and now I do see it should've been a straightforward bet, bet, bet. On the river I decided to try and get a little value, going off the idea that he was loose/passive and that I could safety take a bet/fold line. Definitely could've made it easier on myself by playing it more straightforward though, and I'm aware that this play would crash and burn against more observant opponents, as they rarely call with worse and C/R the river with better (or as a bluff, knowing the flush is very unlikely for my range).
I do stay within a 25-30 buy-in range for whatever limit I'm at; the smaller stack size here was because I had just lost the previous pot, and playing on Bovada you do not have an instant top-up option, so without quick reflexes it can happen from time to time, and I definitely don't move as quick as I once did!

Thank you all for your insights, they were very helpful.

I would cbet this flop. As played, I think we should check back the river after all the action OTT.