Hi Smithrc,
Thanks fot the opinions.
Indeed, there are some look hairy but beheave like female.
For example, I have 7-8 caves in my tank but Zeb No. 1,3,4,8,9,11,14 they stay outside or next to the cave.
Zeb No 6 ,12 and 13 have their own prefer cave and stay in all the time.
I have only 2-3 caves that size are around 3-4cm but others around 5-6cm.
I think maybe this is the reason some male may ignore the cave and stay out of the caves.
Anyway, finger across to see what's going on in the future.

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