. If a second polarizer is set up that is horizontal, what, do you suppose, happens with the vertical component or the light, in general?

Only horizontally polarized light comes out the other side of the filter; all of the rest of the light is blocked by the filter. A black car reflects much less light than a white car.

I’d have to say no because without oxygen in the water the fish would all be dead. so if you want to fish for dead fish, pick the ponds with the lowest oxygen concentrations.