In the past when I had the problem with the tiny flies/Gnats/fruit I used a homemade trap with some vinegar and soap. However when I tried it this time around I had no luck, so I replaced the vinegar with a piece of apple. However that didn't work, they seem to like the sink with the dirty dishes (doing some by hand and waiting on the landlord for a new dishwasher). What else can I put in the traps to try to take down their numbers?