The only opening is a 4cm opening around the auto feeder.
I did add 2 male bristlenose during the week, maybe they spook them during the night, but I think it is more likely to be the fact it is in the loungeroom and a bit more traffic (though I didnt turn the lights on when I came home in the wee hours this morning), maybe the moonlight etc
custom made lids coming up when I move
Steve
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