One situation I often find confusing is when the flop has a flush draw on board which then completes on the turn, particularly when I'm out of position.

For example, we bet the flop with KhQd on Qc7c3s. Our opponent calls, and the turn comes the 8c.

What's the best way to handle this situation? How can we get value from our flushes, bluff, and protect our non-flush hands in a balanced way?

In this article, Matt Janda suggests betting hands like top pair for a small size of about 25% pot. He argues that this is good because it allows us to keep our opponent's range wide.

What I like about this strategy is that it allows us to get value from our non-flush made hands and puts mid-weak flush draws in a tough spot. How can we balance this smaller bet size? I assume we have to include flushes in order to remain uncapped/unexploitable.

Does it make sense to bet all of our continuing hands for a 25% size? I.E. flushes, strong non-flush hands, and bluffs? If we do choose this strategy, what are we doing with hands like KQ when facing a raise? How many bluffs should we incorporate with this size to remain balanced, and how does this change if we plan on bet/folding some of our range?

Basically my question is, is this small bet size a viable strategy in these spots? If so, what's the best way to implement it, and if not, how should we be approaching these spots from a theoretical standpoint?

I think you should lean toward checking. It may also be a good way to get your value since the card favor your opponent.

Honestly I dont understand why you would bet small with a range disadvAntage. I would have to read the book again. But I think the general rule is bet smaller with a strong range.

There isn't enough information here for me to make my exploitative play. If I knew what stakes we we're in I could make a judgement.

You seem to want a GTO answer anyway, but I will give you this advice.

The perfect player would be able to consider every future scenario before it comes about. We're not perfect players, but, when we see a flop like this we are good enough to pre-plan what will happen when the flush does or doesn't come. When you consider how things will go in the future, this flop is screaming to be checked for loads of reasons but I cant be sure with so little information. What I'm saying, is that to make a good decision on this turn we need to make our plan on the flop. If the flush comes we will do x and make/lose y. If the flush doesn't come... etc etc

It s true what yadoula says. I was just answering quick and for simplicity made few assumptions myself like we re 100bb, out of position, relative to positions, opponent still has more suited cards.

When the flush completes on the turn, some of your c-bet combos nosedived in relative strength (e.g. top pair, no draw), some rocketed up the rankings (flush draws that became flushes), some hands that were monsters are still pretty strong (sets), and some picked up some equity (e.g. "airball" c-bets that picked up a backdoor flush draw).
To play the turn correctly, you just have categorize your combos in terms of relative strength and equity vs continuance ranges, and take appropriate actions. Typically that would mean in this context that you barrel with flushes, sets and flush draws, you check-call with showdown value bluffcatchers, and check-fold your "no-hopers".
Quarter pot is probably a good size to use when you're OOP in this spot, since you want villain to call when you have a flush, you want to set a cheap price with your BDFDs, and you also want to be able to call a raise if you have a set that needs to boat up. With hands like KQ (or even AA/KK) with no FD, you're into bluff-catching mode, trying to get to showdown as cheaply as possible. A hand like KQo isn't strong enough to bet for value (it hates getting raised), and it's nonsensical as a bluff (nothing better folds). Ergo, you should check(-call).
This would likely mean you only have a low barreling frequency in this spot, but there are two things I'd point out about that:
1. You shouldn't be c-betting and barreling very often when OOP in general.
2. It's hard to make a flush, whether you're the PFR or the pre-flop caller. Neither player should be betting that turn card at a high frequency, so it's not the case that checking the flushy turn makes you particularly exploitable. (You should also have some tricks up your sleeve, with some check-raises with the nuts, to disincline villain from betting with air).

I think must be careful when saying it s hard to make a flush because you could be biased.

It s relatively hard to make a flush in general.

But if you can only have a range of pocket pairs, very few broadways and suited connectors & suited broadways & suited aces, and the turn complete a flush, and with some of these ranges you decided to call the flop, knowing the turn may bring s flush card. It s not that hard.

I think you must not think only likelihood cards connect, but likelihood certain actions are taken with certain hands.

This was really helpful, thanks. So hands like top pair/overpairs with a flush draw are generally hands to keep betting on the turn? My thought was that they might make better check/calls as they make good bluffcatchers with a flush blocker. If we bet our TP/overpairs with a FD OTT, are we just calling down with all of our overpairs/strongest top pairs even without a blocker?

Also, with what frequency should we be checking the nut flush on the turn looking to check/raise?

Thanks!

i think the idea of betting 25% is stupid, why not check? it accomplishes the same thing.

flush completing turns favour villain so as a default you should be checking most and betting a polar range for a large sizing. you should bet your lower flushes over your Ax flushes since they are more vulnerable and checking some of your nuts helps protect your range. betting sets and some flush draws as well and checking everything else seems like a good baseline to go off

depends on the villain. if you do it and get positive results, keep doing it. make sure and have a continuation plan on the river.

The top pairs and overpairs with flush blockers/backdoors make more sense as turn bets than the hands without flush blockers because they literally have more equity against the calling range, and can even continue if they face a raise. Just consider the difference between AA with a club and AA without one. The former can get called by Qx, TT/99 (with a club) that it's beating, but it still has a draw to the nuts when it's losing to 88, 77 or KJcc/JTcc. AcAx obviously blocks the nut combos of AQcc/AJcc, so there are very few hands that it is losing to. Since AcAx is pretty high in your range, it can be bet for value and get called by worse. If villain raises, you won't fold a draw to the nuts.
But what about AA with no club? It's still beating Qx, but it's drawing dead vs flushes (which it doesn't block at all) and almost dead vs sets. AA with no flush backdoor/blocker is therefore considerably weaker. You don't want to bloat a pot OOP when your equity vs the continuance range is much lower. There's also a decent chance you'll win at showdown if the turn checks through. You're much less likely to win at showdown if you bet AA (no club) and villain doesn't fold. You also hate getting raised on the turn if you potentially have no outs.
When you check-call the turn (with top pair, for example), the river card obviously affects how you play the river, as does villain's bet-size if he chooses to bet. You wouldn't call with all your bluff-catchers on the river (or even the turn), but you'll call with the best ones. It might be the case that KQ (no club) should actually x-fold to a half pot bet on the turn, as you can continue instead with the flushes, sets, overpairs and pairs with a blocker/backdoor that you didn't barrel with. With a well designed checking range, KQo might be so low down your range that you can jettison it as a -EV continue. You'll make so much by check-raising flushes and calling with sets and pr+draws that the hands that won't ever be able to hero-call on the river can be folded on the turn.
One wrinkle I'll add is that you shouldn't necessarily be betting the flop in the first place with various hands that many players would c-bet without a thought. It would be perfectly fine to check the flop with AA/KK and most KQ that don't contain a club blocker. You rarely want to start with a c-bet OOP on boards where you're going to get floated a lot and the turn and river are going to be difficult to navigate.
Sometimes when people ask "What do I do on this horrible turn?" the answer is go back and check the flop.
That's hard to say. It depends what the overall ranges look like and how often you expect villain to bet if you check, but I would think that the nut flushes should be check(-raised) at a very high high frequency. Not only does checking the nuts give you a chance to get two bets in on one street (and try to stack a set or lower flush), it also 'protects' the hands that you really don't want to play for stacks with. (i.e. your check-calling range that has SDV).

Everything always depends on the villain.

actually i think in this case complicating your strategy by adding a random 25% bet size that probably doesn't provide any additional EV depends on you

I agree somewhat. In some spots, flushes can make up a decent proportion of a range. However, I was imagining this spot was something like MP vs BTN, with BTN calling pre with medium pairs, AQ and the suited Broadways you mentioned. When the flop comes Qc 7c 3s, BTN probably only has 4 flush draw combos (AJs, ATs, KJs, JTs). MP has all the nut flush draws in his range along with those same Broadway combos. If hero has the Ac, Jc or Tc blocker, it's really hard for villain to have a flush draw. He's much more likely to have a set or AQo, or an underpair, or AJs, ATs, KQs, KJs, JTs in the wrong suit. To put it another way, at least three quarters of his suited Broadways do not have a flush draw.
If BTN calls on the flop with 77+ and the FDs, he's still only going to have a flush about 10% of the time when the 8c comes on the turn. Around 20% of his range is sets, and the other 70% is one pair that just wants to get to showdown. He's not in love with that turn card, so I don't think he's betting it very often if MP checks to him.
If hero in MP has a low flop c-betting frequency and it contains lots of hands with at least one club, then his turn range might be comprised of as much as 20% flushes, so he could bet them (small) for value (to get called by sets and top pair and TT/99 with the draw/blocker), or he could check-raise to punish a BTN that tries to rep a flush when he rarely actually has it.

I understand, people are not too uniform in their flatting range. Some almost never flat too, and some flat suited aces and connectors a little or much more.