Thx. Pic would help.I made one for my son that worked great with a box shaped plastic bottle. I cut one big side. I then I then cut the sides so the bottom was only held by the remaining side as a hinge. Float it in the tank and get the fish used to swimming into it to eat. Get them comfortable going all the way in then flip up the bottom and they’re caught. If I have another bottle at home I’ll make one quick and post a pic.