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Are maggots in your compost bin good or bad? Every website seems to say a different thing! I know worms are good, but these are baby fly maggots.

I don't think they are such a bad thing. If there are too many flies in my compost bin, I just leave the top off for half an hour. They usually make a bolt for freedom.
The usual cause of flies is too much fruit in the bin.

I think if you have a covered compost bin, like the dalek type, you're not likely to escape a few maggots. The area's dark, warm and full of rotting vegetation - blue bottle paradise

Cold composting - open style - will still get some but not so many.