it was metal
the point was not for seperation of fry, i only ever used to to seperate teenage, or adults into there sexes, for selective breeding. or have a bunch of females who were ready to drop, in one side so the babys could swim through to the other and not be eatin, that way i could fish them out and put them in a maturation tank.
I managed to get a plastic frame kit 1f x 1f from my other hobby shop (modeling trains) of which the frame fit perfectly with no gaps into the middle of the tank. then all i did was sylicon the mesh to the frame.
Shae 250