I installed a system about 6 months ago, shortly before it started getting cold for winter here in new mexico and so far is working great. No smell when i open the tank to top up the organic material. However, now that the weather is warming up i noticed flies coming in and out of the tank. So my question is does the tank need airflow? I could put weather stripping on the lid to prevent the flies from entering and exiting. But does the tank itself need to breath?
Thanks in advance
Since this is an aerobic system then yes, it does need to breathe. You could achieve that via a screened vent pipe though, which might stop the flies getting in to lay eggs?