Yellow watchman goby

[bwitchn]

My 29 gal Biocube glass cover has two small triangular openings facing front of the tank on each corner of the glass (beveled) that is how it is from factory, should I cover it if I get a yellow watchman goby? Is there a risk it could jump from that small opening.

 

[kaxt]

I have had a few fish in past tanks get out of small holes before. It always amazed me that the whole top of the tank can be covered and sure enough a fish finds the one 1/2 inch hole that is open to get through.

I always say cover as much as you possibly can, better safe than sorry.

 

[ryeguyy84]

I thought those holes were for air exchange. I took my glass cover off because of heat and the glass was always covered in condensation.