One could take the fish out with the rock (if it is jammed in there) and drop the fish in a photo tank = can be any glass jar with a flat front or a small tank, like a 5 gal or 10 gal.
What do you mean? I catch large fish often in an old pillowcase. Small ones that get stuck in the net can be caught with a plastic bag or a large cup / jar, etc. or in a piece of a PVC pipe when it hides in there.
Holes are to small for my hand

Is there anything these guys, really go crazy for? I fed the mosquito larva the other day, and they enjoyed that. Basically i have 3, 1 Eupterus, the hybrid, and then this little guy.
The Hybrid and Eupterus, is out alot. How ever this guy.. He sometimes bursts around, but never stands still, or anything like that. Mostly its just in its rock.
While i get a picture, wich will most likely be tomorrow, ill give you describtion, even tho i most likely wont help. Maybe it will remind you of one, and you can post a picture:
About 10cm, maybe not fully grown. Dark brown, darker than the hybrid. Small spots, smaller than eupterus. And the fins are, darker than the rest of it (Not black) and with a white glare.
Maybe i remember wrong about the fins.'
A couple of years ago, i used to feed them something i dont remember, i think it was either prawns, or cichlid pellets. They could go crazy for that, but lately, they dont enjoy the prawns, i mean they eat them but not agressively, and the cichlid pellets, i changed brand i think.