Flies in Tank. Phorid flies?

[Kaiju]

The phorid flies are a problem as a dead cricket is suitable for reproduction and creating more of these pain in the necks. They will also infest wounds or scratches on frogs, egg masses or even newly hatched reptiles (infecting through the umbilicus) as well as feeder insect cultures.

I've had issues with phorid flies for months. I've tried so many things I'm about ready to pull my hair out.

Tank: 10g with coconut fibre (currently with just paper towel changed daily). Plastic lid with one 5x3 inch opening.
Inhabitants: 1 tomato frog
Contains: one water dish changed daily.
Humidity and temperature: 80% and 76F respectfully.

I changed the fibre and bleached the tank twice but the flies are all over the house. I already have little cups with vinegar and seran wrap with holes punched in the top. They die in there buti t doesn't seem to be making a dent.

I want to have a nice set up again, but the flies and maggots keep coming back. please help me. :c