If your code is still as it is up above then they are not isolated. Everything that you do to the rectangle will also happen to the fish.
Once you get the Push and Pops set up correctly then all you have to do is move them around with a keyboard control. I think that you should set your z values to something more reasonable. Right now the rectangles Z values are more than 30x bigger than the model's X and Y positions. Until you get this straightened out you might want to dial the Z positions down to something like 0.5, or 1.0. so they are proportional with everything else, at least until you've got the setup working properly.