My polys don't seem to use their eyes much when looking for food anyway. LOL They'll pass a dang worm several times, within centimeters, before finding it. Not the brightest crew in the world but still effective. I think they use their smell much more.
Oh,, it may very well be from a rub on a net but still work on the water as others have said.
Oh,, it may very well be from a rub on a net but still work on the water as others have said.