A previous model I designed used a piece of cloth or paper to allow gases to escape while keeping the bugs out of my one-gallon kombucha jar.
It occurs to me a similar goal could be achieved with a tight infill. So, I returned to the model and created new parts to cover the lid holes. These new parts will have a 95% infill (different from the rest of the piece) without top or bottom layers. That way, they will act as a sieve or filter allowing the air and gases to go through, but it will be too small for any bug. The final part can also be washed.
I printed the lid out of PETG filament on a textured sheet on my MK3.
I have been using the lid for over half a year for a weekly brew with no issues.
The author marked this model as their own original creation.