The first one I assumed was a fluke. After a while, I went to feed my PCFs. When I opened the tube and began tapping it to knock the Hydei into my dusting deli cup immediately fully functional melanogaster flies swarmed out. Today I noticed Melanogaster Maggots in my Hydei tube. I dont know how, but theyre getting in and outperforming the larger flies in reproduction, rendering the cultures pretty useless. Only thing I can think to do is freeze the culture then add more flightless flies from another tube. Any ideas on how theyre making it in(its probably as simple as a fly or two flying in when I open it) and what to do about it would be great. The first tube functioned for quite a while bfore being invaded, but the tube I just bought was colonized much faster.