“Sink” flies. Ideas about how to get rid of them?

[Marie6762]

My home-share doesn’t include kitchen use, but on a case-by-case basis, limited use has worked out happily for all.

Last November I was surprised at a gradual reappearance of “fruit flies” after successfully getting rid of them a couple seasons prior.  I simply stopped keeping fruit out.  This time the  flies were a tiny bit larger than fruit flies or gnats and mostly contained to the kitchen sink area.  Rarely found anywhere else in the house.

Well, it’s now almost April and, despite varied & prodigious efforts, they are still a problem.  I have explained them away as “fruit flies” and gotten sympathetic smiles (never a complaint, as they aren’t in the guest spaces) - BUT: eeewwww and😤, I am beyond fed up.

 I don’t use toxins (bleach is my “big gun”) and wish not to, but will if I absolutely must.  Here is what I’ve already tried:

clean drained once a week with vinegar, baking soda, boiling water.  Sometimes sub bleach for vinegar& soda

keep sink & area freakishly clean, empty food trap with every crumb or so. Keep Area as dry as possible

wash down areas where they alite (?) lite? With bleach solution

fly paper ( yes, even with guests around. 😟 Caught one single, tiny fly in one week.  So,  no to that mess.

spritz bleach solution at them 😏

poured gasoline down the drain and set it on fire

The last one was to see if you’re paying attention but, who knows what I may be driven to?

Any experience, wisdom or hope for me?  I’d be happy to hear toxic options as well, since it may be coming to that…

[Emiel1]

@Marie6762 

"poured gasoline down the drain and set it on fire"

And now not only the fruit flies, but also the drain has gone ?

[Mark116]

@Marie6762  Drain flies [which look like tiny moths] and fruit flies are two different things.  If you have drain flies, increase the cleaning of the drain with the baking soda/vinegar/lot of boiling water to every day for 1 week and see if that helps.  If they are fruit flies then there must be some other source in the kitchen area, check behind the appliances, clean the trash cans and don't leave any kind of food out on the counters.  That's all I can think of.

[Debra300]

https://www.thisoldhouse.com/pest-control/21339927/how-to-get-rid-of-drain-flies

[Lorna170]

@Marie6762   I am a bit more reactive than most, and will go full out on the piping.  If you are not handy, or don't have a handy partner, have a plumber come in and uncouple your drain pipes and U joint and clean them thoroughly.  Of course, if you have lit the pipes on fire, you may need new pipes.

Do you have a garbage disposal?